Translation:Which is the biggest bag that you sell?
Is "Where is the biggest bag you sell?" acceptable?
I know Mana = "Where", Yang Mana = "Which" but since the "Yang" is separated from the "Mana" I'm not sure which applies.
To me, either one works. You're asking them to indicate which bag is their biggest. In English, perhaps it's not correct to say "Where is your biggest bag" but I think that's what I hear more often than "Which" in this case. I really think both translations work though.