Purchase tickets and join the fans at a game at San Van Dong Duong Dong Stadium. If there's nothing happening while you're there, you might like to check if there's a tour of the grounds.
When you've finished at this Duong Dong sporting facility, why not check out Phu Quoc Night Market, Phu Quoc Beach, and Dinh Cau? They're not far from San Van Dong Duong Dong Stadium and also a favorite with tourists.