Trust is defined as the belief that people will stick to a set of predetermined agreement on how to behave and act to achieve a shared goal. With trust, things can accelerate more smoothly, and you can easily predict or calculate the next move. Without trust, more variables will enter the decision making algorithm, lengthening the process and increasing risk.
In Vietnam, unfortunately, there seems to be a trust crisis. For example, when buying food at the market, even from accredited merchants, people still doubt if the product is safe to eat. When encountering beggars or street vendors on the street, people worry if they are really poor and need help, or they just try to milk and live off people's sympathy. There are many campaigns asking for donation for various causes which turn out to be fake and end up benefiting scammers. Even with administrative procedures, the practice is also shady, and gives opportunities for corruption.
It is a tough question but I do wonder how to build trust?!