Best shopping? Your best bet is to buy traditional Vietnamese handicraft. Don't buy clothings or things that you can get in US because the quality is not as nice. In my opinion, Vietnamese make the best lacquer painting with inlay mother of pearl. Price is not going to be problem but look for quality. The painting should be smooth, i.e. the mother of pearl should be inlay and not just glue on top of the lacquer. Other posibilities are hand painted silk, hand made clothes, traditional Vietnamese musical instruments.