VU 305 then VZ 106 at Bangkok
Hanoi → Bangkok → Chiang Mai
Timetable, Bangkok time
14:10VU 305 from Hanoi at the gate
13:50VZ 106 to Chiang Mai leaves the gate
23 h 40 apart on the timetable, overnight
VZ 106 leaves 23 h 40 after VU 305 arrives on the timetable: more than half a day, so not a connection we count.