Qualify for 144 hours visa free from HK to Guangzhou

So you will travel to Guangzhou from HK, then take a flight from HK to Vietnam? I have to tell you that it's not an eligible route for the 144. To use the 144, you need to fly to Guangzhou, then after the 144 fly from Guangzhou to Vietnam. And you need the flight ticket and hotel reservation to get the 144.

To make it easier, you may apply for a China visa in HK in advance.