Fly from Vienna to Hanoi

Hellou, I'm flying to Vietnam with my husband. from Vienna we have a technical stop in Urumchi for 2 hours and then a stopover in Guangzhou 23 hours and then continue to Hanoi. The 72-hour visa also applies to us or not? I don't know because we have 2 stops in China (urumchi + canton) together 25 hours.