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.
Researched and applied in production since 1975 in the form of tablets, in 2004 changed to hard capsule dosage form, then added syrup for children, powder and bath water for prevention and treatment of flu and cold very effectively.