Exporting doSearch from classes, and removed unnecesary qdb param

src/utils/classes.ts

@@ -564,6 +564,7 @@ if (!isMainThread) {
 
       try {
         qdbs.forEach((qdb) => {
+          // FIXME: === 0?
           if (searchIn.length === 0 || searchIn.includes(qdb.index)) {
             const res = doSearch(
               qdb.data,
@@ -639,4 +640,5 @@ export {
   createQuestion,
   addQuestion,
   dataToString,
+  doSearch,
 }