What about the tourist card to Vietnam? I can cancel it when I come back. What is the price? Can you give me a detailed answer? ?

It is best to travel abroad to Vietnam with dual-card dual-standby mobile phones. Shenzhou card is useless. You can dial 10086 globally, but the cost is very expensive, about 10 yuan/minute, and few people use it.

Suggestion:

If you buy a Vietnamese mobile phone card at the Sino-Vietnamese border, you can use it directly in China's mobile phone, and then tell your family the Vietnamese mobile phone number. You can send a message of 1 yuan/message when a Vietnamese mobile phone calls back to 2 yuan in China for about one minute, or you can send a message directly to a Vietnamese mobile phone on China mobile phone +0084 at the same cost.