Never heard anything like that and I am Polish so you couldn't hear it from medias.
"Tak noh pravda" which I would guess means Yes, quite true".
Doubt it.it sounds weird to agree 3 times in 3 words sentence.Polish person would say "Tak, to prawda","No,prawda"'or simply "prawda".
Phonetically, it is something like: "Tak noh pravda"
I guess you mean "Taka prawda".
I'm fairly sure there's an N in it,
Since you insist on "N" then it must be "Gówno prawda" what means "this is not true" but you don't want to speak this kind of language.