Some expats talk about the "lazy Vietnamese husband" syndrome which is basically the idea that Vietnamese husbands are lazy because their wives always take care of them.
There are clearly defined lines between men and women, and what is expected from each of them.
Vietnamese women think of their husbands as their ultimate priority and will see you as #1 in their life.
This means that a Vietnamese wife will expect to be kept busy, and if not she might become frustrated.
Just let her know that she doesn’t need to do everything on her own, although this can be a problem because Vietnamese women don't want their men to be seen doing "women's" work.
For a single guy really looking for a Vietnamese wife, or girlfriend, it means that when you get one-on-one time with a Viet girl it really does count for something.