This is what I normally do.

1. Find exact model that match your criteria. Use criteria search available in GSM Arena
   http://www.gsmarena.com/search.php3
   For example you want a 13MP camera, 5″ screen size, 2GB RAM, 16GB Internal storage etc.
2. Then look for price of the phone in lazada.com.my or in mudah.my
3. When you are shopping outside in the mall, at least you know what’s the price range for the model that you are looking for.