I'm a bit confused and I have a question and I'm asking for your help.

I am a Croatian citizen with the passport and I booked a flight with China Southern airlines from Vienna to Bangkok with two stops, first in Urumqi with connecting time for 4h 55 min and second in Guangzhou with connecting time for 2h 50 min.

Can someone please provide me with the information do I need a visa for that time at the airports? For Urumqi says you don't need if it's no longer than 2h.
Maybe someone who already flew this destination?
Thanks,
Iva