As China marks the 90th anniversary of the Red Army’s victory in the Long March, some young Chinese are looking to the historic journey for guidance as they face uncertainty in their lives and future. For Lyu Leiyiyi, a 22-year-old student at the Communication University of China, the spirit of the Long March offers a sense of stability at a time when people and the environment around her are changing at a dizzying pace. “People in their 20s are going through a period of uncertainty,” Lyu said....