…’은’ === $end1 && $len > 2 ) { $term = substr( $term, 0, -1 ); } elseif ( ‘에’ === $end1 && $len > 2 ) { $term = substr( $term, 0, -1 ); } elseif ( ‘는’ === $end1 && $len > 2 ) { $term = substr(…Korean has postpositions, which complicate things for Relevanssi. Fortunately, it’s easy to clean up the most common postpositions from the words. Add this function to your site: add_filter( ‘relevanssi_stemmer’, ‘relevanssi_korean_plural_stemmer’ ); function relevanssi_korean_plural_stemmer( $term ) { $len = strlen( $term ); $end1 = substr( $term, -1, 1 ); if (……0, -1 ); } elseif ( ‘의’ === $end1 && $len > 2) { $term = substr( $term, 0, -1 ); } return $term; } After you’ve added this function, rebuild the index. You also need to adjust the minimum word length to 2, as many Korean words are only…