diff --git a/application/Espo/Core/SelectManagers/Base.php b/application/Espo/Core/SelectManagers/Base.php
index 28b5f2f5a8..e4014e2f96 100644
--- a/application/Espo/Core/SelectManagers/Base.php
+++ b/application/Espo/Core/SelectManagers/Base.php
@@ -1646,7 +1646,7 @@ class Base
 
             if (!$skipWidlcards) {
                 if (
-                    strlen($textFilter) >= $textFilterContainsMinLength
+                    mb_strlen($textFilter) >= $textFilterContainsMinLength
                     &&
                     (
                         $attributeType == 'text'
diff --git a/application/Espo/ORM/DB/Query/Base.php b/application/Espo/ORM/DB/Query/Base.php
index 54be559fe3..538cf46144 100644
--- a/application/Espo/ORM/DB/Query/Base.php
+++ b/application/Espo/ORM/DB/Query/Base.php
@@ -336,7 +336,7 @@ abstract class Base
         }
 
         $columns = substr($rest, 0, $delimiterPosition);
-        $query = substr($rest, $delimiterPosition + 1);
+        $query = mb_substr($rest, $delimiterPosition + 1);
 
         $columnList = explode(',', $columns);