Use the services of the certified dealers, you can try Vietnam Visa Online or Vietnam E Visa. To receive Vietnam visa upon arrival you need to buy an “Approval letter”. This approval letter can be purchased from any of these companies and then you need to take this filled letter to Vietnam. You obtain the official visa at the airport in Vietnam. This procedure applies if you fly to Vietnam by plane (Hanoi, Ho Chi Minh City, Da Nang). If you come from a neighboring country, for example by bus or motorbike, this visa does not apply.