What is the meaning of this?
You (yourself) are yuck!
Sam're yuck
"Fuj" is the equivalent of "ew" or "eurgh" in English - it is usually said to show that you are disgusted by something.
"Sam jestes fuj" means something like "no, YOU are disgusting (or "ew")". The "sam" at the beginning implies that the person who said this phrase was called disgusting earlier by the person they are addressing.
You are disgusting
