I guess nobody cares about political bad blood in this thread,coz that's not what they're here for,right?
I honestly don't think it holds water to use the four guys whose nationality you have known before as examples to corroborate the claim that you can tell the differences between polish people and russian people.
If you meet a russian guy on the street today and you immediately know where he's from by his looks,then you can really tell.
P.S. I would've never known their nationality,if I hadn't seen their faces beforehand.