" In both casual and polite contexts, this phrase is used in response to thanks. It essentially has the same meaning as "you're welcome."  Pronounce the saying as doh ee-tah-shee mah-she-teh.  In non-romanized form, write the phrase out as どういたしまして。 Informally, instead of "dough itashimashite", you can say "iie", pronounced "e-yeh" written いいえ, which literally just means "no."  By doing so, you are just telling the person who helped you "it was nothing,' or "No thank you."

How would you rephrase that briefly using Vietnamese?
Đáp lại bằng câu "dou itashi mashite.