I found a similar issue trying to expand the search with the archive addon. The actual archive page itself uses a javascript search query that appears to only search by title. Could not get it to look at package descriptions.
However, if you use the [wpdm-search-page] shortcode that comes with the wpdm directory add-on, THAT searches into the description. I only discovered that shortcode by going through the source code for the archive php file. The section to describe that area is on line 364. I then rewrote that to include categories and ended up with something like this: $res = $wpdb->get_results(“select * from {$wpdb->prefix}ahm_files where title like ‘%$_REQUEST[q]%’ or description like ‘%$_REQUEST[q]%’ or category like ‘%$_REQUEST[q]%'”,ARRAY_A);
Since my site is for downloads only, and nothing else, I ended up rewriting the search.php page in my theme template area using this information to create a search bar on the site itself that parses the data out to a new page.
Anyway, I hope this can help you some as it took me about 2 days to get it all sorted out for my own site.
