In the 70s of the last century, Pharmacist Hy Van Lang - Former director of Yen Bai Pharmaceutical Company (Ypharco) and his associates traveled throughout the northern mountains in search of an ancient remedy "for cross-fragmentation". With the combination of precious medicinal herbs and the life-saving secrets of famous highland doctors, they are recorded, prepared and summarized in a convenient pill form of Cam Xuyen Huong Yen Bai.