Su Qin and Zhang Yi were both famous strategists in Chinese history, and their biographies were widely circulated. If you want to find the biographies of Su Qin and Zhang Yi, you can look for related books in the library or online bookstores. Some common biographies of Su Qin and Zhang Yi included historical books such as Records of the Historian, Warring States Strategy, and Zi Zhi Tong Jian. He could also use search engines to search for relevant online resources such as Baidu Encyclopedia and wikipedia to learn more about Su Qin and Zhang Yi.