Si deseamos que el buscador nativo de WordPress busque únicamente en los títulos de los post, hay que añadir el fichero functions.php del tema las siguientes líneas:
/** * Search SQL filter for matching against post title only. * * @link http://wordpress.stackexchange.com/a/11826/1685 * * @param string $search * @param WP_Query $wp_query */ function wpse_11826_search_by_title( $search, $wp_query ) { if ( ! empty( $search ) && ! empty( $wp_query->query_vars['search_terms'] ) ) { global $wpdb; $q = $wp_query->query_vars; $n = ! empty( $q['exact'] ) ? '' : '%'; $search = array(); foreach ( ( array ) $q['search_terms'] as $term ) $search[] = $wpdb->prepare( "$wpdb->posts.post_title LIKE %s", $n . $wpdb->esc_like( $term ) . $n ); if ( ! is_user_logged_in() ) $search[] = "$wpdb->posts.post_password = ''"; $search = ' AND ' . implode( ' AND ', $search ); } return $search; } add_filter( 'posts_search', 'wpse_11826_search_by_title', 10, 2 ); // End Search SQL