Uln, wuh, xmn
 

I'm working on an itinerary from the US through Ulaanbaatar, Wuhan and Xiamen. I'm finding that United/Air China have by far the lowest rates, but I've never been satisfied with their economy product. I'm trying to use Korean if possible to for the TPAC portion, but am not having much luck at getting a reasonable price. Any suggestions??

IIRC, its possible to fly nonstop between ICN and both ULN and XMN. If I were in your shoes, I'd try for an open jaw along these lines.

ULN-WUH will almost certainly require a connection in PEK. AFIK, there aren't many discounts in the ULN-PEK market, so you'll need to throw down $300 on that segment (or else use UA miles for ULN-PEK-WUH). Assuming you don't use UA miles, that leaves two intra-China segments: PEK-WUH and WUH-XMN. I suggest you book both of these once you arrive in China.