Search | Type: PHPSearch Results on Different Search Template

When you need a custom search results template for a CPT.

function template_chooser($template) {
     global $wp_query;
     $post_type = get_query_var('post_type');
     if( $wp_query->is_search && $post_type == 'clients' ) {
         return locate_template('page_clients.php');
     }
     return $template;
}
add_filter('template_include', 'template_chooser');