I want to travel by bus from Lanzhou to Lixian county Gansu then from Lixian to Yulin, Shaanxi provin. Any advice?

Inside the Xin Dong Bu Shi Chang (New East Market 新东部市场), you can find buses to reach Lixian County at 08:00, 12:00 and 18:00.

From Lixian to Yulin, there is no direct bus and you still need to transfer in Lanzhou. But I am sorry that I am not very clear about the bus schedule and you are suggested to go to the Lanzhou Bus Station to consult.