I studied in India 2012 for a short time. I met incredible smart and hardworking people. However, one thing that I found quite unnerving was that there is a tendency to always anwser yes if asked if one knows how to do something, even if thats not true. Sometimes a plain "I don't know" can be very helpful in achieving a goal. I can't count how many times I asked a rickshaw driver if he knew a certain place and he ans…
I believe it is similar in Vietnamese culture. When we work with them they often say yes only for us to find out later that they had no clue what to do.
You have to adjust your questions. Always start the question with a W, and never with a Has or Is.