5 letter names are intersections on airways, arrivals or departures. TABDO sounds like one of those. 2 letters could either be taxiway intersections or radio beacons so depending on who said it would give you a clue. I did happen to find ZB, it is a beacon in the town of Zhob. That was a lucky find since I don't have aviation charts for that part of the world any more.
seems to carry lots of information about Navaids around the world