Can someone explain me difference between ''wieś'' and ''znać''?
Znać - to know a person/place/thing; to be acquainted with someone/something.
Wiedzieć - to know a fact about something/someone/someplace.
I don’t know if it is a general rule, but "znać" you usually use before a noun, while "wiedzieć" you use before some particles. For example:
znam Beatę = I know Beata
wiem o Beacie = I know about Beata
znam wieś = I know the village
wiem o wsi = I know about the village
znam powód katastrofy = I know the reason of the catastrophe
wiem czemu doszło do katastrofy = I know why the catastrophe had happened
(you can say it also by using "przez co" (because of what) or "dlaczego" (for what reason) instead of "czemu")
hope it will give you some intuition ;)