Products are not showing search results

Hello Team, 
Thanks for plugin its working fine but currently its only searching in pages and posts but not in Products. I added your code too in function.php but still same

// Add custom post types to search
add_filter('wpnlweb_searchable_post_types', function($post_types) {
    $post_types[] = 'product';
    return $post_types;
});

Can you help me out 
Thanks