Try these,

http://www.bayt.com/en/job-search-results/?keyword=stores&jb_loc_list=qa...

http://www.gulftalent.com/home/index.php

You can also try to visit the official site of each store you wish to work with, and find if there are openings. Try not to limit yourself to a store or two, apply in as many as you can, you don’t know which one will end up responding.

I’m not sure if recession actually has hit Qatar, so just stay positive, all will be well.

Very best of luck
Salam