4
Humm, there is more than that, what is not working!
If you ask for a popular combination as eg Russian - English, then the first 20 of a lot of search results are shown. At the bottom there is a page navigator, which 'forget' the required language pair and on the next page lists some users.
Maybe try by replacing with the original 2.2 search.php
(PS your site is extremely slow at loading > 30s)