Hi, the idea is to use wpfts_index_post hook to extract the special meta-field (added by RCWD) value and index the file which is linked there.

The working code is below.

add_filter('wpfts_index_post', function($index, $post) { global $wpfts_core; if ($post && $wpfts_core && function_exists('get_field')) { if ($post->post_type == 'paper') { // You can change the post_type here $file = get_field('file', $post->ID); // You can change the ACF field name here if (isset($file['path']) && (strlen($file['path']) > 0)) { // Add a special library to work with file contents (included to WPFTS Pro) require_once $wpfts_core->root_dir.'/includes/wpfts_utils.class.php'; // This call will return extracted text from the FILE $ret = WPFTS_Utils::GetCachedFileContent_ByLocalLink($file['path'], false, true); // Store the content to separate index cluster (so we can apply different relevance weight to it, if required) $index['rcwd_file_content'] = isset($ret['post_content']) ? trim($ret['post_content']) : ''; } } } return $index; }, 3, 2);

Looks not that hard?

Also, you can download the ready addon plugin here.