The Vietnamese are shy, humble, many don’t speak english so its difficult to engage a conversation. In general I didn’t have any issues photographing them and only a couple of times my request was refused.
I saw this old lady in Sapa, seat by the road and smiling to everyone. I asked the guide to get her permission to photograph. She covered her face laughing saying she was too old and too ugly. At the end I managed to get her posing to me and when I finished I placed some money in her calloused hand thankfully. She kissed my hand, and that touched me a lot.