Language / Negation in Polish sentences [12]

Hello I am teaching myself Polish from a textbook. I've come across sentences in the negation lesson that I just can't figure out.

Could someone help me with these sentences?

1. Nic nie wiem, on o tym nigdy nic nie mowi. (this sentence is very confusing to me!)
2. On nigdy na nic nie ma czasu. (He never has time for anything. Is this correct?)
3. Komu Staszek o tym mówił? (Who did Staszek speak to about it. correct?)
4. Temu dziecku nikt nigdy niczym nie pomoga. (No one ever helps that child with anything. Correct?)
5. O czym dziadek dzieciom opowiadał? (Did the grandfather tell the child something? Is this correct?)
6. Ta nauczycielka nie uczy żadnego z naszych dzieci.
7. Ktoś mi coś mówił o tych dzieciach. (Someone told me something about those kids. correct?)
8. Może one wiedzą o kimś, kto wraca do Krakowa.

Any help appreciated.

Language / The Polish word for fart? [28]

Hello, all my dad's grandparents came from Poland and my own grandparents were raised in Chicago speaking polish. Unfortunately my dad didn't learn much of the language, but he always used the polish word for fart which he pronounced as boo-it-ki. I am now studying polish and looked up fart to see how it is spelled, but only came up with the word bąk and bąki which is kind of similar. Was my dad just horribly mispronouncing the word or is booitki an archaic (great grandparent's time) form?

Also now that I think of it, we used to call my dad's grandmother, my great grandmother busha. I looked up grandma in the dictionary, but only find babka or babcia. Is this another corruption from my family or are these actual words?