Actually "dari mana kamu?" and "kamu dari mana?" are the same question regardless of the position of "kamu/you".
We, Indonesian, had a tendency to throw grammar out of window and just proceed to ignore its whole existence when we communicated with each other and still able to understand the context of conversation.
No you don't. Your grammar is just different. Alternatively you could say that every native speaker ignores grammar's existence, and yet effortlessly nails it.
Similarly many Chinese claim their language has no grammar only to be confused by foreigners' incorrect grammar.