Answer:
A random search from Dubai (DXB) to Ho Chi Minh City (SGN) shows:
OPTION 1: 12hr 20min via Kuala Lumpur (KUL)
DXB - KUL Malaysia Airlines Flt 161 Dep 06:40pm 23Sep,Thu (Stops in Karachi)
KUL - SGN Malaysia Airlines Flt 750 Dep 09:05am 24Sep,Fri (Nonstop)
Flight Duration: 11hr 05min; Layover Time: 1hr 15min; Total Trip Time: 12hr 20min
OPTION 2: 12hr 20min via Guangzhou (CAN)
DXB - CAN China Southern Airlines Flt 384 Dep 01:40am 23Sep,Thu
CAN - SGN China Southern Airlines Flt 4703 Dep 03:15pm 23Sep,Thu
Operated by Vietnam Airlines
Flight Duration: 10hr 35min; Layover Time: 1hr 45min; Total Trip Time: 12hr 20min