How to restrict Astra search to ONLY WooCommerce Products

add_filter( 'get_search_form', 'astra_get_search_form_callback' );
function astra_get_search_form_callback( $search_form ) {
$search_form = str_replace( '-1">', '-1"/><input type="hidden" name="post_type" value="product"/>', $search_form );
return $search_form;
}