Things I can't get at my local supermarket:

• brown sugar
• tinfoil (alumin(i)um foil)
• baking paper
• paper towels
• can opener
• sponges (for cleaning)
  
• fish sauce (although there's a possibility that I can't read the fish sauce bottle).

I have made trips especially for almost all of these items, only to stand around in what I think are the appropriate aisles and not be able to find what I want. 

We currently need (subjective) all of these things, except for the brown sugar, which I found at the other market on the same street.  Couldn't find any of the other things, though.