Search stopped working in prestashop 1.6.17

[MariuszDeveloper]

Hello,

I have a problem with working application of prestashop 1.6.1.17

Application uses default-bootstrap theme.

Search suddenly stopped working. Autocomplete is not working and php search as well is not working. Only finds categories of products but not products.

Ajax request is ok but returns empty array even if i make errors in search.php or search controller.

Indexing  works. At least there is no error. 

I reinstaled boxsearch module.

I replaced search.php class found in one of the topics here.

I tried to die or var_dump  in search controller or search.php but its not appearing in browser.

I need your help,

Thank You