Restrict searches to posts only

//* Restrict searches to posts only
add_filter( 'pre_get_posts', 'bourncreative_search_filter' );
function bourncreative_search_filter( $query ) {

    if ( $query->is_search && ! is_admin() && $query->is_main_query() ) {
          $query->set( 'post_type', 'post' );
    }

    return $query;

}