diff --git a/src/DataSource/ArrayDataSource.php b/src/DataSource/ArrayDataSource.php
index e66fe234..3730e3e8 100644
--- a/src/DataSource/ArrayDataSource.php
+++ b/src/DataSource/ArrayDataSource.php
@@ -151,7 +151,7 @@ protected function applyFilter($row, Filter $filter)
 				$row_value = strtolower(Strings::toAscii((string) $row[$column]));
 
 				foreach ($words as $word) {
-					if (strpos($row_value, strtolower(Strings::toAscii((string) $word))) !== false) {
+					if (strpos($row_value, strtolower(Strings::toAscii($word))) !== false) {
 						return $row;
 					}
 				}