diff --git a/apps/sodo-search/src/search-index.js b/apps/sodo-search/src/search-index.js
index a70595e42d..89f9dcf363 100644
--- a/apps/sodo-search/src/search-index.js
+++ b/apps/sodo-search/src/search-index.js
@@ -15,7 +15,8 @@ export default class SearchIndex {
                 id: 'id',
                 index: ['title', 'excerpt'],
                 store: true
-            }
+            },
+            ...this.#getEncodeOptions()
         });
         this.authorsIndex = new Flexsearch.Document({
             tokenize: 'forward',
@@ -23,7 +24,8 @@ export default class SearchIndex {
                 id: 'id',
                 index: ['name'],
                 store: true
-            }
+            },
+            ...this.#getEncodeOptions()
         });
         this.tagsIndex = new Flexsearch.Document({
             tokenize: 'forward',
@@ -31,7 +33,8 @@ export default class SearchIndex {
                 id: 'id',
                 index: ['name'],
                 store: true
-            }
+            },
+            ...this.#getEncodeOptions()
         });
 
         this.init = this.init.bind(this);
@@ -133,4 +136,17 @@ export default class SearchIndex {
             tags: this.#normalizeSearchResult(tags)
         };
     }
+
+    #getEncodeOptions() {
+        const regex = new RegExp(
+            `[\u{4E00}-\u{9FFF}\u{3040}-\u{309F}\u{30A0}-\u{30FF}\u{AC00}-\u{D7A3}\u{3400}-\u{4DBF}\u{20000}-\u{2A6DF}\u{2A700}-\u{2B73F}\u{2B740}-\u{2B81F}\u{2B820}-\u{2CEAF}\u{2CEB0}-\u{2EBEF}\u{30000}-\u{3134F}\u{31350}-\u{323AF}\u{2EBF0}-\u{2EE5F}\u{F900}-\u{FAFF}\u{2F800}-\u{2FA1F}]|[0-9A-Za-zа-я\u00C0-\u017F\u0400-\u04FF\u0600-\u06FF\u0980-\u09FF\u1E00-\u1EFF]+`,
+            'mug'
+        );
+
+        return {
+            encode: (str) => {
+                return ('' + str).toLowerCase().match(regex) ?? [];
+            }
+        };
+    }
 }