I want that my search page give results of posts (that i want that show) and taxonomy

The code to get just two type of posts:

function searchfilter($query) {

      if ($query->is_search && !is_admin() ) {
          $query->set('post_type',array('lesson','series'));
      }
 return $query;
}

add_filter('pre_get_posts','searchfilter');

I want it to look for taxonomy too
Thanks