No matter who, what, how: dù … cũng

To say "no matter who, what, where or how", put dù before a question word, and cũng before the verb in the second half: Dù ai nói gì thì em cũng không đổi ý. No matter what anyone says, I won't change my mind. Thì often marks where the second half begins, and vẫn (still) can take the place of cũng.

The question words are the usual ones: dù đi đâu (wherever you go), dù xa tới đâu (however far), dù bao nhiêu tiền (whatever it costs). Đi nữa or đi chăng nữa at the end of the first half makes it stronger: Dù đi đâu đi nữa, em cũng nhớ Sài Gòn.

You know a question word with cũng for "every": ai cũng, gì cũng. Dù turns it into "no matter". In quick speech it's often left out: Mấy giờ anh về em cũng chờ. Whatever time you get home, I'll wait. Thế nào … cũng, "however it goes", means "surely, one way or another": Thế nào ảnh cũng tới. He'll turn up, you'll see.

Dù sao is a set phrase for "anyway, in any case": Dù sao cũng cảm ơn anh. Thanks anyway. With a plain sentence instead of a question word, dù means "even if" or "although": Dù trời mưa, em vẫn đi.