Somebody told me a long time ago that you find a girl....when you stop looking....I think its true...But you could try the local bars and meeting places...Statistics , if you believe them say that the best place to meet a girl , is in the supermarket....!
Don't know you nor what you look like but I agree stop looking...women sense that. Put yourself out there in public, always smile and say hello to the women too. Good luck!!
Back when i was holidaying in poland, i met girls (around my age) without a problem. In fact almost everywhere i went. Naturally this for me was completely different to anything i had experienced before. I wasnt even looking for girls, they just happened.
Now i forgot what the moral of my story was... Basically my suggestion is being outgoing. Being constantly on the move and doing something could help in finding someone. As suggested, join a recreational/sports club of your interest. Personally, I wouldn't go looking for people in pubs.
Actually it was just the name of The Doors Song I was listening to. Now I'm listening to one called This is the End which obviously is useful when the relationship falls apart. All part of the added value
Sofia and rooster are not exactly the kind of place you're going to find a girlfriend (although you'll certainly find women there who'll sleep with you, for a price).
Get a copy of Warsaw In Your Pocket and then read the bar reviews, there are much better choices than the places you list.