Hi Zlamushka,

As far as I know adding a label will allow you (someone else) to find all posts with that label. Therefore if you add both label to a post (like Curry Pastes, Malay) the post will appear in both hmmm....categories ?..but wait, here is the problem.
I don't know how you create the left menu, but I suppose the labels are added there automatically. And that means there is no label category (because there is impossible to "magically" know what label to which category belongs). If it would have been possible to choose categories for labels or even for posts, than probem is solved.

Of course, another idea would be to create the menu yourself and to manually link to posts there.

Hope that helps !
Radu