Hiep Thai is a supermarket in Garland catering to the area's sizeable Vietnamese population, differentiating it from other large Asian groceries like Asia World and Hong Kong Market. Their selection of things like Japanese snacks is smaller, but they have more selection in products like fish sauce and other Vietnamese specialties. They carry specialty meats and fresh fish, as well as a wide variety of fruit drinks. There's at least one aisle dedicated to items for use at home altars. Prices are reasonable, probably cheaper than other markets, actually.
In front of the actual grocery store, they also have a video rental place with Vietnamese movies and shows, as well as Korean and Japanese entertainment dubbed into Vietnamese. You have to take out a membership, though, so it's kind of expensive. There's also a Lollicup convenient for you to refresh yourself while you shop, and a restaurant.