"Dieuh neh lio moh sai-loh" is a Cantonese phrase and is a very derogatory statement.
Considering that someone might have used that phrase at you and you want to know the meaning - it is very inappropriate and refers to the other person's mother.
If you are a teenager or child, please report it to someone older whom you trust. Do not indulge in verbal fight with the person who said it to you.