i think you can use any word of them because they have the same meaning but different dialect

Второй вариант в египетском диалекте чаще означает "не умею".

They're the same but in different dialects In Egypt we say msh b3raf :D = I don't know

That was a very helpful answer, Manar. Note that you could have answered directly (by the pink button) rather than limit it to the comment section. I've just realized that the only reason why the Shami and MSA variants differ from each other is because the Shami indicative imperfect verb requires a "b-" prefix and because, when acting as a pronoun rather than a participle, "maa" means "not" rather than "what." Doesn't look so different and complicated now.

all these are negative form for saying "i don`t know " but , in different arabic dialect "مابعرف" syrian dialect "مش بعرف " Egyptian dialect "بعرفش" used in many arab country "لا اعرف " standard arabic