How to restrict search on a certain page to only return results against custom taxonomies?

Question

On a specific page, I would like the search to be performed only against the terms from two custom taxonomies. Not the content or title. That is, the user is directly searching taxonomy terms.

What I'm trying to do is completely rewrite the query for searches, but it doesn't seem to work.

function search_filter_get_posts($query) {
    if ( !$query->is_search )
        return $query;

    $terms = explode(",", $query->query['s']);

    $taxquery = array(
        'post_type' => 'eproduct',
        'tax_query' => array(
            'relation' => 'OR',
            array(
                'taxonomy' => 'product-type',
                'field'    => 'slug',
                'terms'    => $terms,
            ),
            array(
                'taxonomy' => 'product-features',
                'field'    => 'slug',
                'terms'    => $terms,
            ),
        ),
    );
;
 $query = new WP_Query( $taxquery );

}
add_action( 'pre_get_posts', 'search_filter_get_posts' );

Answer 1

You did not return the new $query; that's why it's not working for you.

$query = new WP_Query( $taxquery );    
return $query;

Answer 2

I think, the problem is that you just put filtered query in $query variable but did not set it in the main query i.e. $query->set()

See if this works in your code -

$query->set( 'tax_query', $taxquery );

instead of

$query = new WP_Query( $taxquery );