Jiuquan Town
Outside Tianshuiji, an old man seemed to be looking for something. The music he sang was so sad and sad that it made people cry.
If you come here to talk to Guo Jiazheng who is wandering, you can get the next clue: try your luck at a place that sells musical instruments.
When you come here, pick up the ancient long flute standing on the shelf next to the pipa girl, then go back to talk to Guo Jiazheng. After two conversations, you can complete the task.
Note: Selecting Happy to Serve at the end will enter the playing mode, but selecting Xiao is in your hand will not, and will not affect the rewards.