search results (tags) in all languages

Hi,
I added the following snippet to functions.php to include the tag search

add_action( 'pre_get_posts', 'include_tags_in_search' );
function include_tags_in_search($query){
    if($query->is_search){
        $terms = explode(' ', $query->get('s'));
        $query->set('tax_query', array(
            'relation'=>'OR',
            array(
                'taxonomy'=>'post_tag',
                'field'=>'slug',
                'terms'=>$terms
            )
        ));
    }
}

It works but the search results include results from all languages. What should I add to the snippet to filter only the results of the language in which I search? Thanks