diff --git a/README.md b/README.md
index 7f269f1..b029b76 100644
--- a/README.md
+++ b/README.md
@@ -67,31 +67,31 @@ Plugins (extern projects):
     </tr>
     <tr>
         <td>flexsearch.bundle.js</td>
-        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.3/dist/flexsearch.bundle.js" target="_blank">Download</a></td>
-        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.bundle.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.bundle.js</a></td>
+        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.31/dist/flexsearch.bundle.js" target="_blank">Download</a></td>
+        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.bundle.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.bundle.js</a></td>
     </tr>
     <tr></tr>
     <tr>
         <td>flexsearch.light.js</td>
-        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.3/dist/flexsearch.light.js" target="_blank">Download</a></td>
-        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.light.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.light.js</a></td>
+        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.31/dist/flexsearch.light.js" target="_blank">Download</a></td>
+        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.light.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.light.js</a></td>
     </tr>
     <tr></tr>
     <tr>
         <td>flexsearch.compact.js</td>
-        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.3/dist/flexsearch.compact.js" target="_blank">Download</a></td>
-        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.compact.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.compact.js</a></td>
+        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.31/dist/flexsearch.compact.js" target="_blank">Download</a></td>
+        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.compact.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.compact.js</a></td>
     </tr>
     <tr></tr>
     <tr>
         <td>flexsearch.es5.js *</td>
-        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.3/dist/flexsearch.es5.js" target="_blank">Download</a></td>
-        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.es5.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.3/dist/flexsearch.es5.js</a></td>
+        <td><a href="https://github.com/nextapps-de/flexsearch/raw/0.7.31/dist/flexsearch.es5.js" target="_blank">Download</a></td>
+        <td><a href="https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.es5.js" target="_blank">https://rawcdn.githack.com/nextapps-de/flexsearch/0.7.31/dist/flexsearch.es5.js</a></td>
     </tr>
     <tr></tr>
     <tr>
         <td>ES6 Modules</td>
-        <td><a href="https://minhaskamal.github.io/DownGit/#/home?url=https://github.com/nextapps-de/flexsearch/tree/0.7.3/dist/module/" target="_blank">Download</a></td>
+        <td><a href="https://minhaskamal.github.io/DownGit/#/home?url=https://github.com/nextapps-de/flexsearch/tree/0.7.31/dist/module/" target="_blank">Download</a></td>
         <td>The <i>/dist/module/</i> folder of this Github repository</td>
     </tr>
 </table>
@@ -106,7 +106,7 @@ npm install flexsearch
 
 #### Get Latest Nightly (Do not use for production!)
 
-Just exchange the version number from the URLs above with "master", e.g.: "/flexsearch/__0.7.3__/dist/" into "/flexsearch/__master__/dist".
+Just exchange the version number from the URLs above with "master", e.g.: "/flexsearch/__0.7.31__/dist/" into "/flexsearch/__master__/dist".
 
 ### Compare Web-Bundles
 
@@ -438,7 +438,7 @@ const worker = new WorkerIndex(options);
 
 Or via CDN:
 ```html
-<script src="https://cdn.jsdelivr.net/gh/nextapps-de/flexsearch@0.7.3/dist/flexsearch.bundle.js"></script>
+<script src="https://cdn.jsdelivr.net/gh/nextapps-de/flexsearch@0.7.31/dist/flexsearch.bundle.js"></script>
 ```
 
 AMD:
@@ -447,7 +447,7 @@ AMD:
 var FlexSearch = require("./flexsearch.js");
 ```
 
-Load one of the builds from the folder <a href="https://github.com/nextapps-de/flexsearch/tree/0.7.3/dist">dist</a> within your html as a script and use as follows:
+Load one of the builds from the folder <a href="https://github.com/nextapps-de/flexsearch/tree/0.7.31/dist">dist</a> within your html as a script and use as follows:
 
 ```js
 var index = new FlexSearch.Index(options);
diff --git a/dist/flexsearch.bundle.js b/dist/flexsearch.bundle.js
index 44da61a..aa8610d 100644
--- a/dist/flexsearch.bundle.js
+++ b/dist/flexsearch.bundle.js
@@ -1,5 +1,5 @@
 /**!
- * FlexSearch.js v0.7.3 (Bundle)
+ * FlexSearch.js v0.7.31 (Bundle)
  * Copyright 2018-2022 Nextapps GmbH
  * Author: Thomas Wilkerling
  * Licence: Apache-2.0
@@ -7,7 +7,7 @@
  */
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diff --git a/dist/flexsearch.compact.js b/dist/flexsearch.compact.js
index bd67b3c..c8d5508 100644
--- a/dist/flexsearch.compact.js
+++ b/dist/flexsearch.compact.js
@@ -1,5 +1,5 @@
 /**!
- * FlexSearch.js v0.7.3 (Compact)
+ * FlexSearch.js v0.7.31 (Compact)
  * Copyright 2018-2022 Nextapps GmbH
  * Author: Thomas Wilkerling
  * Licence: Apache-2.0
diff --git a/dist/flexsearch.debug.js b/dist/flexsearch.debug.js
index 05b4a3d..ef62e50 100644
--- a/dist/flexsearch.debug.js
+++ b/dist/flexsearch.debug.js
@@ -1,5 +1,5 @@
 /**!
- * FlexSearch.js v0.7.3 (Debug)
+ * FlexSearch.js v0.7.31 (Debug)
  * Copyright 2018-2022 Nextapps GmbH
  * Author: Thomas Wilkerling
  * Licence: Apache-2.0
@@ -216,12 +216,12 @@ K.prototype.del = function(a) {
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-function pa(a, b, c, d, e, f) {
+function pa(a, b, c, d, e, f, g) {
   setTimeout(function() {
-    const g = a(c, JSON.stringify(f));
-    g && g.then ? g.then(function() {
-      b.export(a, b, c, d, e + 1);
-    }) : b.export(a, b, c, d, e + 1);
+    const h = a(c ? c + "." + d : d, JSON.stringify(g));
+    h && h.then ? h.then(function() {
+      b.export(a, b, c, e, f + 1);
+    }) : b.export(a, b, c, e, f + 1);
   });
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@@ -502,7 +502,7 @@ L.prototype.export = function(a, b, c, d, e) {
     default:
       return;
   }
-  pa(a, b || this, c ? c + "." + f : f, d, e, g);
+  pa(a, b || this, c, f, d, e, g);
   return !0;
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 L.prototype.import = function(a, b) {
@@ -859,20 +859,20 @@ R.prototype.export = function(a, b, c, d, e) {
       g.export(a, b, e ? f : "", d, e++) || (d++, e = 1, b.export(a, b, f, d, e));
     });
   } else {
-    let f;
+    let f, g;
     switch(e) {
       case 1:
-        c = "tag";
-        f = this.tagindex;
+        f = "tag";
+        g = this.tagindex;
         break;
       case 2:
-        c = "store";
-        f = this.store;
+        f = "store";
+        g = this.store;
         break;
       default:
         return;
     }
-    pa(a, this, c, d, e, f);
+    pa(a, this, c, f, d, e, g);
   }
 };
 R.prototype.import = function(a, b) {
diff --git a/dist/flexsearch.es5.js b/dist/flexsearch.es5.js
index a93a10d..e6e479d 100644
--- a/dist/flexsearch.es5.js
+++ b/dist/flexsearch.es5.js
@@ -1,5 +1,5 @@
 /**!
- * FlexSearch.js v0.7.3 (ES5)
+ * FlexSearch.js v0.7.31 (ES5)
  * Copyright 2018-2022 Nextapps GmbH
  * Author: Thomas Wilkerling
  * Licence: Apache-2.0
@@ -20,7 +20,7 @@ y("Object.is",function(a){return a?a:function(b,c){return b===c?0!==b||1/b===1/c
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 a.boost;this.map=g?ha(f):D();this.m=f=e.resolution||1;this.h=g?ha(f):D();this.G=c&&c.G||a.rtl;this.K=(b=a.matcher||d&&d.K)&&ma(b,!1);this.L=(b=a.stemmer||d&&d.L)&&ma(b,!0);if(c=b=a.filter||d&&d.filter){c=b;d=D();e=0;for(f=c.length;e<f;e++)d[c[e]]=1;c=d}this.filter=c;this.cache=(b=a.cache)&&new M(b)}t=N.prototype;t.append=function(a,b){return this.add(a,b,!0)};
 t.add=function(a,b,c,d){if(b&&(a||0===a)){if(!d&&!c&&this.register[a])return this.update(a,b);b=this.encode(b);if(d=b.length){for(var f=D(),g=D(),e=this.depth,h=this.F,k=0;k<d;k++){var l=b[this.G?d-1-k:k],p=l.length;if(l&&p>=this.C&&(e||!g[l])){var n=O(h,d,k),m="";switch(this.H){case "full":if(2<p){for(n=0;n<p;n++)for(var q=p;q>n;q--)if(q-n>=this.C){var r=O(h,d,k,p,n);m=l.substring(n,q);P(this,g,m,r,a,c)}break}case "reverse":if(1<p){for(q=p-1;0<q;q--)m=l[q]+m,m.length>=this.C&&P(this,g,m,O(h,d,k,
 p,q),a,c);m=""}case "forward":if(1<p){for(q=0;q<p;q++)m+=l[q],m.length>=this.C&&P(this,g,m,n,a,c);break}default:if(this.o&&(n=Math.min(n/this.o(b,l,k)|0,h-1)),P(this,g,l,n,a,c),e&&1<d&&k<d-1)for(p=D(),m=this.m,n=l,q=Math.min(e+1,d-k),r=p[n]=1;r<q;r++)if((l=b[this.G?d-1-k-r:k+r])&&l.length>=this.C&&!p[l]){p[l]=1;var u=this.l&&l>n;P(this,f,u?n:l,O(m+(d/2>m?0:1),d,k,q-1,r-1),a,c,u?l:n)}}}}this.s||(this.register[a]=1)}}return this};
@@ -31,7 +31,7 @@ function xa(a,b,c,d,f,g,e,h){var k=[],l=h?a.h:a.map;a.B||(l=za(l,e,h,a.l));if(l)
 function za(a,b,c,d){c?(d=d&&b>c,a=(a=a[d?b:c])&&a[d?c:b]):a=a[b];return a}t.contain=function(a){return!!this.register[a]};t.update=function(a,b){return this.remove(a).add(a,b)};
 t.remove=function(a,b){var c=this.register[a];if(c){if(this.s)for(var d=0,f;d<c.length;d++)f=c[d],f.splice(f.indexOf(a),1);else Q(this.map,a,this.F,this.B),this.depth&&Q(this.h,a,this.m,this.B);b||delete this.register[a];if(this.cache)for(b=this.cache,c=0;c<b.h.length;c++)f=b.h[c],d=b.cache[f],d.includes(a)&&(b.h.splice(c--,1),delete b.cache[f])}return this};
 function Q(a,b,c,d,f){var g=0;if(a.constructor===Array)if(f)b=a.indexOf(b),-1!==b?1<a.length&&(a.splice(b,1),g++):g++;else{f=Math.min(a.length,c);for(var e=0,h;e<f;e++)if(h=a[e])g=Q(h,b,c,d,f),d||g||delete a[e]}else for(e in a)(g=Q(a[e],b,c,d,f))||delete a[e];return g}t.searchCache=ua;
-t.export=function(a,b,c,d,f){switch(f||(f=0)){case 0:var g="reg";if(this.s){var e=D();for(var h in this.register)e[h]=1}else e=this.register;break;case 1:g="cfg";e={doc:0,opt:this.B?1:0};break;case 2:g="map";e=this.map;break;case 3:g="ctx";e=this.h;break;default:return}wa(a,b||this,c?c+"."+g:g,d,f,e);return!0};t.import=function(a,b){if(b)switch(E(b)&&(b=JSON.parse(b)),a){case "cfg":this.B=!!b.opt;break;case "reg":this.s=!1;this.register=b;break;case "map":this.map=b;break;case "ctx":this.h=b}};ra(N.prototype);function Aa(a){a=a.data;var b=self._index,c=a.args,d=a.task;switch(d){case "init":d=a.options||{};a=a.factory;b=d.encode;d.cache=!1;b&&0===b.indexOf("function")&&(d.encode=Function("return "+b)());a?(Function("return "+a)()(self),self._index=new self.FlexSearch.Index(d),delete self.FlexSearch):self._index=new N(d);break;default:a=a.id,b=b[d].apply(b,c),postMessage("search"===d?{id:a,msg:b}:{id:a})}};var Ba=0;function R(a){if(!(this instanceof R))return new R(a);var b;a?G(b=a.encode)&&(a.encode=b.toString()):a={};(b=(self||window)._factory)&&(b=b.toString());var c="undefined"===typeof window&&self.exports,d=this;this.A=Ca(b,c,a.worker);this.h=D();if(this.A){if(c)this.A.on("message",function(f){d.h[f.id](f.msg);delete d.h[f.id]});else this.A.onmessage=function(f){f=f.data;d.h[f.id](f.msg);delete d.h[f.id]};this.A.postMessage({task:"init",factory:b,options:a})}}S("add");S("append");S("search");
+t.export=function(a,b,c,d,f){switch(f||(f=0)){case 0:var g="reg";if(this.s){var e=D();for(var h in this.register)e[h]=1}else e=this.register;break;case 1:g="cfg";e={doc:0,opt:this.B?1:0};break;case 2:g="map";e=this.map;break;case 3:g="ctx";e=this.h;break;default:return}wa(a,b||this,c,g,d,f,e);return!0};t.import=function(a,b){if(b)switch(E(b)&&(b=JSON.parse(b)),a){case "cfg":this.B=!!b.opt;break;case "reg":this.s=!1;this.register=b;break;case "map":this.map=b;break;case "ctx":this.h=b}};ra(N.prototype);function Aa(a){a=a.data;var b=self._index,c=a.args,d=a.task;switch(d){case "init":d=a.options||{};a=a.factory;b=d.encode;d.cache=!1;b&&0===b.indexOf("function")&&(d.encode=Function("return "+b)());a?(Function("return "+a)()(self),self._index=new self.FlexSearch.Index(d),delete self.FlexSearch):self._index=new N(d);break;default:a=a.id,b=b[d].apply(b,c),postMessage("search"===d?{id:a,msg:b}:{id:a})}};var Ba=0;function R(a){if(!(this instanceof R))return new R(a);var b;a?G(b=a.encode)&&(a.encode=b.toString()):a={};(b=(self||window)._factory)&&(b=b.toString());var c="undefined"===typeof window&&self.exports,d=this;this.A=Ca(b,c,a.worker);this.h=D();if(this.A){if(c)this.A.on("message",function(f){d.h[f.id](f.msg);delete d.h[f.id]});else this.A.onmessage=function(f){f=f.data;d.h[f.id](f.msg);delete d.h[f.id]};this.A.postMessage({task:"init",factory:b,options:a})}}S("add");S("append");S("search");
 S("update");S("remove");function S(a){R.prototype[a]=R.prototype[a+"Async"]=function(){var b=this,c=[].slice.call(arguments),d=c[c.length-1];if(G(d)){var f=d;c.splice(c.length-1,1)}d=new Promise(function(g){setTimeout(function(){b.h[++Ba]=g;b.A.postMessage({task:a,id:Ba,args:c})})});return f?(d.then(f),this):d}}
 function Ca(a,b,c){try{var d=b?eval('new (require("worker_threads")["Worker"])("../dist/node/node.js")'):a?new Worker(URL.createObjectURL(new Blob(["onmessage="+Aa.toString()],{type:"text/javascript"}))):new Worker(E(c)?c:"worker/worker.js",{type:"module"})}catch(f){}return d};function T(a){if(!(this instanceof T))return new T(a);var b=a.document||a.doc||a,c;this.I=[];this.h=[];this.m=[];this.register=D();this.key=(c=b.key||b.id)&&U(c,this.m)||"id";this.s=C(a.fastupdate);this.o=(c=b.store)&&!0!==c&&[];this.store=c&&D();this.D=(c=b.tag)&&U(c,this.m);this.l=c&&D();this.cache=(c=a.cache)&&new M(c);a.cache=!1;this.A=a.worker;this.async=!1;c=D();var d=b.index||b.field||b;E(d)&&(d=[d]);for(var f=0,g,e=void 0;f<d.length;f++)g=d[f],E(g)||(e=g,g=g.field),e=F(e)?Object.assign({},
 a,e):a,this.A&&(c[g]=new R(e),c[g].A||(this.A=!1)),this.A||(c[g]=new N(e,this.register)),this.I[f]=U(g,this.m),this.h[f]=g;if(this.o)for(a=b.store,E(a)&&(a=[a]),b=0;b<a.length;b++)this.o[b]=U(a[b],this.m);this.index=c}function U(a,b){for(var c=a.split(":"),d=0,f=0;f<c.length;f++)a=c[f],0<=a.indexOf("[]")&&(a=a.substring(0,a.length-2))&&(b[d]=!0),a&&(c[d++]=a);d<c.length&&(c.length=d);return 1<d?c:c[0]}function V(a,b){if(E(b))a=a[b];else for(var c=0;a&&c<b.length;c++)a=a[b[c]];return a}
@@ -42,5 +42,5 @@ t.remove=function(a){F(a)&&(a=V(a,this.key));if(this.register[a]){for(var b=0;b<
 t.search=function(a,b,c,d){c||(!b&&F(a)?(c=a,a=""):F(b)&&(c=b,b=0));var f=[],g=[],e,h=0;if(c)if(c.constructor===Array){var k=c;c=null}else{a=c.query||a;k=(e=c.pluck)||c.index||c.field;var l=c.tag;var p=this.store&&c.enrich;var n="and"===c.bool;b=c.limit||b||100;var m=c.offset||0;if(l&&(E(l)&&(l=[l]),!a)){g=0;for(e=void 0;g<l.length;g++)if(e=Da.call(this,l[g],b,m,p))f[f.length]=e,h++;return h?f:[]}E(k)&&(k=[k])}k||(k=this.h);n=n&&(1<k.length||l&&1<l.length);for(var q=!d&&(this.A||this.async)&&[],r=
 0,u=void 0,A=void 0,x=void 0;r<k.length;r++)if(x=void 0,A=k[r],E(A)||(x=A,A=x.field,a=x.query||a,b=x.limit||b),q)q[r]=this.index[A].searchAsync(a,b,x||c);else{d?u=d[r]:u=this.index[A].search(a,b,x||c);x=u&&u.length;if(l&&x){var z=[],B=0;n&&(z[0]=[u]);var Z=0,H=void 0;for(H=void 0;Z<l.length;Z++)if(H=l[Z],x=(H=this.l[H])&&H.length)B++,z[z.length]=n?[H]:H;B&&(u=n?sa(z,b||100,m||0):ta(u,z),x=u.length)}if(x)g[h]=A,f[h++]=u;else if(n)return[]}if(q){var La=this;return new Promise(function(Ma){Promise.all(q).then(function(Na){Ma(La.search(a,
 b,c,Na))})})}if(!h)return[];if(e&&(!p||!this.store))return f[0];l=0;for(m=void 0;l<g.length;l++){m=f[l];m.length&&p&&(m=Ea.call(this,m));if(e)return m;f[l]={field:g[l],result:m}}return f};function Da(a,b,c,d){var f=this.l[a],g=f&&f.length-c;if(g&&0<g){if(g>b||c)f=f.slice(c,c+b);d&&(f=Ea.call(this,f));return{tag:a,result:f}}}function Ea(a){for(var b=Array(a.length),c=0,d;c<a.length;c++)d=a[c],b[c]={id:d,doc:this.store[d]};return b}t.contain=function(a){return!!this.register[a]};t.get=function(a){return this.store[a]};
-t.set=function(a,b){this.store[a]=b;return this};t.searchCache=ua;t.export=function(a,b,c,d,f){f||(f=0);d||(d=0);if(d<this.h.length){var g=this.h[d],e=this.index[g];b=this;setTimeout(function(){e.export(a,b,f?g:"",d,f++)||(d++,f=1,b.export(a,b,g,d,f))})}else{switch(f){case 1:c="tag";var h=this.l;break;case 2:c="store";h=this.store;break;default:return}wa(a,this,c,d,f,h)}};
+t.set=function(a,b){this.store[a]=b;return this};t.searchCache=ua;t.export=function(a,b,c,d,f){f||(f=0);d||(d=0);if(d<this.h.length){var g=this.h[d],e=this.index[g];b=this;setTimeout(function(){e.export(a,b,f?g:"",d,f++)||(d++,f=1,b.export(a,b,g,d,f))})}else{switch(f){case 1:var h="tag";var k=this.l;break;case 2:h="store";k=this.store;break;default:return}wa(a,this,c,h,d,f,k)}};
 t.import=function(a,b){if(b)switch(E(b)&&(b=JSON.parse(b)),a){case "tag":this.l=b;break;case "reg":this.s=!1;this.register=b;a=0;for(var c;a<this.h.length;a++)c=this.index[this.h[a]],c.register=b,c.s=!1;break;case "store":this.store=b;break;default:a=a.split("."),c=a[0],a=a[1],c&&a&&this.index[c].import(a,b)}};ra(T.prototype);var Ga={encode:Fa,G:!1,H:""},Ha=[J("[\u00e0\u00e1\u00e2\u00e3\u00e4\u00e5]"),"a",J("[\u00e8\u00e9\u00ea\u00eb]"),"e",J("[\u00ec\u00ed\u00ee\u00ef]"),"i",J("[\u00f2\u00f3\u00f4\u00f5\u00f6\u0151]"),"o",J("[\u00f9\u00fa\u00fb\u00fc\u0171]"),"u",J("[\u00fd\u0177\u00ff]"),"y",J("\u00f1"),"n",J("[\u00e7c]"),"k",J("\u00df"),"s",J(" & ")," and "];function Fa(a){var b=a=""+a;b.normalize&&(b=b.normalize("NFD").replace(la,""));return ja.call(this,b.toLowerCase(),!a.normalize&&Ha)};var Ja={encode:Ia,G:!1,H:"strict"},Ka=/[^a-z0-9]+/,Oa={b:"p",v:"f",w:"f",z:"s",x:"s","\u00df":"s",d:"t",n:"m",c:"k",g:"k",j:"k",q:"k",i:"e",y:"e",u:"o"};function Ia(a){a=Fa.call(this,a).join(" ");var b=[];if(a)for(var c=a.split(Ka),d=c.length,f=0,g,e=0;f<d;f++)if((a=c[f])&&(!this.filter||!this.filter[a])){g=a[0];for(var h=Oa[g]||g,k=h,l=1;l<a.length;l++)g=a[l],(g=Oa[g]||g)&&g!==k&&(h+=g,k=g);b[e++]=h}return b};var Qa={encode:Pa,G:!1,H:""},Ra=[J("ae"),"a",J("oe"),"o",J("sh"),"s",J("th"),"t",J("ph"),"f",J("pf"),"f",J("(?![aeo])h(?![aeo])"),"",J("(?!^[aeo])h(?!^[aeo])"),""];function Pa(a,b){a&&(a=Ia.call(this,a).join(" "),2<a.length&&(a=I(a,Ra)),b||(1<a.length&&(a=na(a)),a&&(a=a.split(" "))));return a||[]};var Ta={encode:Sa,G:!1,H:""},Ua=J("(?!\\b)[aeo]");function Sa(a){a&&(a=Pa.call(this,a,!0),1<a.length&&(a=a.replace(Ua,"")),1<a.length&&(a=na(a)),a&&(a=a.split(" ")));return a||[]};K["latin:default"]=pa;K["latin:simple"]=Ga;K["latin:balance"]=Ja;K["latin:advanced"]=Qa;K["latin:extra"]=Ta;var Y=self,Va,Wa={Index:N,Document:T,Worker:R,registerCharset:function(a,b){K[a]=b},registerLanguage:function(a,b){qa[a]=b}};(Va=Y.define)&&Va.amd?Va([],function(){return Wa}):Y.exports?Y.exports=Wa:Y.FlexSearch=Wa;}(this));
diff --git a/dist/flexsearch.light.js b/dist/flexsearch.light.js
index b1a9fd2..3e1a1c9 100644
--- a/dist/flexsearch.light.js
+++ b/dist/flexsearch.light.js
@@ -1,5 +1,5 @@
 /**!
- * FlexSearch.js v0.7.3 (Light)
+ * FlexSearch.js v0.7.31 (Light)
  * Copyright 2018-2022 Nextapps GmbH
  * Author: Thomas Wilkerling
  * Licence: Apache-2.0
diff --git a/dist/module/serialize.js b/dist/module/serialize.js
index 74b1519..9e98b07 100644
--- a/dist/module/serialize.js
+++ b/dist/module/serialize.js
@@ -1 +1 @@
-import{IndexInterface,DocumentInterface}from"./type.js";import{create_object,is_string}from"./common.js";function async(a,b,c,d,e,f){setTimeout(function(){const g=a(c,JSON.stringify(f));g&&g.then?g.then(function(){b.export(a,b,c,d,e+1)}):b.export(a,b,c,d,e+1)})}export function exportIndex(a,b,c,d,e){let f,g;switch(e||(e=0)){case 0:if(f="reg",this.fastupdate)for(let a in g=create_object(),this.register)g[a]=1;else g=this.register;break;case 1:f="cfg",g={doc:0,opt:this.optimize?1:0};break;case 2:f="map",g=this.map;break;case 3:f="ctx",g=this.ctx;break;default:return;}return async(a,b||this,c?c+"."+f:f,d,e,g),!0}export function importIndex(a,b){b&&(is_string(b)&&(b=JSON.parse(b)),"cfg"===a?this.optimize=!!b.opt:"reg"===a?(this.fastupdate=!1,this.register=b):"map"===a?this.map=b:"ctx"===a?this.ctx=b:void 0)}export function exportDocument(a,b,c,d,e){if(e||(e=0),d||(d=0),d<this.field.length){const c=this.field[d],f=this.index[c];b=this,setTimeout(function(){f.export(a,b,e?c:"",d,e++)||(d++,e=1,b.export(a,b,c,d,e))})}else{let b,c;switch(e){case 1:b="tag",c=this.tagindex;break;case 2:b="store",c=this.store;break;default:return;}async(a,this,b,d,e,c)}}export function importDocument(a,b){if(b)switch(is_string(b)&&(b=JSON.parse(b)),a){case"tag":this.tagindex=b;break;case"reg":this.fastupdate=!1,this.register=b;for(let a,c=0;c<this.field.length;c++)a=this.index[this.field[c]],a.register=b,a.fastupdate=!1;break;case"store":this.store=b;break;default:a=a.split(".");const c=a[0];a=a[1],c&&a&&this.index[c].import(a,b);}}
\ No newline at end of file
+import{IndexInterface,DocumentInterface}from"./type.js";import{create_object,is_string}from"./common.js";function async(a,b,c,d,e,f,g){setTimeout(function(){const h=a(c?c+"."+d:d,JSON.stringify(g));h&&h.then?h.then(function(){b.export(a,b,c,e,f+1)}):b.export(a,b,c,e,f+1)})}export function exportIndex(a,b,c,d,e){let f,g;switch(e||(e=0)){case 0:if(f="reg",this.fastupdate)for(let a in g=create_object(),this.register)g[a]=1;else g=this.register;break;case 1:f="cfg",g={doc:0,opt:this.optimize?1:0};break;case 2:f="map",g=this.map;break;case 3:f="ctx",g=this.ctx;break;default:return;}return async(a,b||this,c,f,d,e,g),!0}export function importIndex(a,b){b&&(is_string(b)&&(b=JSON.parse(b)),"cfg"===a?this.optimize=!!b.opt:"reg"===a?(this.fastupdate=!1,this.register=b):"map"===a?this.map=b:"ctx"===a?this.ctx=b:void 0)}export function exportDocument(a,b,c,d,e){if(e||(e=0),d||(d=0),d<this.field.length){const c=this.field[d],f=this.index[c];b=this,setTimeout(function(){f.export(a,b,e?c:"",d,e++)||(d++,e=1,b.export(a,b,c,d,e))})}else{let b,f;switch(e){case 1:b="tag",f=this.tagindex;break;case 2:b="store",f=this.store;break;default:return;}async(a,this,c,b,d,e,f)}}export function importDocument(a,b){if(b)switch(is_string(b)&&(b=JSON.parse(b)),a){case"tag":this.tagindex=b;break;case"reg":this.fastupdate=!1,this.register=b;for(let a,c=0;c<this.field.length;c++)a=this.index[this.field[c]],a.register=b,a.fastupdate=!1;break;case"store":this.store=b;break;default:a=a.split(".");const c=a[0];a=a[1],c&&a&&this.index[c].import(a,b);}}
\ No newline at end of file
diff --git a/package.json b/package.json
index e8e6f21..62a73f7 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "flexsearch",
-  "version": "0.7.3",
+  "version": "0.7.31",
   "description": "Next-Generation full text search library with zero dependencies.",
   "homepage": "https://github.com/nextapps-de/flexsearch/",
   "author": "Thomas Wilkerling",
diff --git a/src/serialize.js b/src/serialize.js
index e7496ae..072e8c5 100644
--- a/src/serialize.js
+++ b/src/serialize.js
@@ -3,11 +3,11 @@
 import { IndexInterface, DocumentInterface } from "./type.js";
 import { create_object, is_string } from "./common.js";
 
-function async(callback, self, key, field, index_doc, index, data){
+function async(callback, self, field, key, index_doc, index, data){
 
     setTimeout(function(){
 
-        const res = callback(key, JSON.stringify(data));
+        const res = callback(field ? field + "." + key : key, JSON.stringify(data));
 
         // await isn't supported by ES5
 
@@ -84,7 +84,7 @@ export function exportIndex(callback, self, field, index_doc, index){
             return;
     }
 
-    async(callback, self || this, field ? field + "." + key : key, field, index_doc, index, data);
+    async(callback, self || this, field, key, index_doc, index, data);
 
     return true;
 }
@@ -188,7 +188,7 @@ export function exportDocument(callback, self, field, index_doc, index){
                 return;
         }
 
-        async(callback, this, key, index_doc, index, data);
+        async(callback, this, field, key, index_doc, index, data);
     }
 }