TPE to Chengdu to South Korea...South Korea to Chengdu to USA

Hello,
All of these tickets would be based on Multi-city flight tickets. I am planning on flying from Taipei to Chengdu directly, stay for 72 hours and then fly to South Korea. Is it possible to fly from South Korea, back to Chengdu for another 72 hours, and then to the USA? From what I have researched, I don't see why it wouldn't be OK if the flight tickets are completely different all multi-city and all one-way tickets.

Thanks!