Well. I hired a web-developer to edit my filters a bit. He did his work well and everything seemed to be fine.
Then (about 30 hours have passed) I was editing some stuff in the menu, adding products and suddenly (I didnt touch anything concerning filters, neither the developer did) all the filters stoped working.
The Developer was only editing the "display" function of the class hikashopCursorClass of the file
administrator/components/com_hikashop/classes/filter.php
At least he was granted acces only to this "classes" folder via FTP.
Now, when you take a look at the site
domsveta.by
and go to the "Catalogue" menu, you will see the products but when you will try to filter by ANY parameter you will get nothing in the filter result.
I don't know whose fault it is. Not of the developer for sure, because I used the backup file of the "filter.php" and nothing changed.
Please, I badly need the help, I wasted about 4 monthsto get the site finished. And now when I finished, the core of the site has stopped working.