Searh engine doesn't works

Hello!
I'm testing this module, and I have an issue, all works fine, permissions, users can view the documents and folders, download it and more. But they can't search nothing, they put more than 3 characters in the search box and presses "enter" or clicks the search button but nothing happens. If I update to the dev version the search engine seems to work fine ( I say seems, because in dev version my users can't access the module although they have permissions).
Thanks!