In case you need to replace certain whole words that the user enters to others (like synonyms), then use this custom code.
What is this, and where do I put this custom code?
add_filter( 'asp_query_args', 'asp_replace_search_keywords', 10, 2 );function asp_replace_search_keywords( $args, $id ) {/*** Add as many words as you want. On the left side place the* word or words separated by comma to replace.* To the right side, place the single word to replace it with.*/$replace = array('word1' => 'word2', // Replace 'word1' with 'word2''word3, word4' => 'word5' // Replace 'word3' and 'word4' with 'word5');// ----------------------------------------// Do not change anything below this line// ----------------------------------------foreach ( $replace as $k => $w ) {$kr = explode(',', $k);foreach ($kr as $krk => &$krv) {$krv = trim($krv);if ( $krv == '' ) {unset($kr[$krk]);} else {$krv = '/\b' . $krv . '\b/u';}}if ( count($krv) > 0 ) {$args['s'] = preg_replace($kr, $w, $args['s']);}}return $args;}
Follow the instructions within the code to add/remove lines to the $replace array variable. Each key is a keyword or keywords separated by comma, and each value is the substitue keyword.