The Fifteen Billion Pound Railway

In a village called Tai-gia-ha lived a well-known and romantic fool. People called him "Yao". People in the village worried about him. They worried that who could take care of him forever and whom he got to spend his life with. Even so, he somehow owned lots of stories with someone. In an evening three months ago, Yao got lost because he ran an errand for his dad to buy him tofu pudding for his childhood's sweetheart. For these months without Yao, Xia and Shuei have lived in the contradiction and self-blaming of reuniting each other and losing Yao. In the meantime, Yao met a troupe director named "bearded man". In the end, how did Yao, seemingly growing up in one night after leaving his home, get back to Tai-gia-ha?