Why do residents in Southeast Asia call the Mekong River "the mother of hope"

The Mekong River originates from the northeast slope of Tanggula Mountain in China, and is called Lan-ts'ang Chiang in China. After it flows into Indo-China Peninsula, it is called Mekong River. The Mekong River, with a total length of 4,880 kilometers, is the most important transnational water system in Asia and the seventh largest river in the world. The main source is Zhaqu, which originated in Zaduo County, Yushu Tibetan Autonomous Prefecture, Qinghai Province, China. It flows through China, Laos, Myanmar, Thailand, Cambodia and Vietnam, and flows into the South China Sea in Ho Chi Minh City, Vietnam. Except China and Myanmar, this basin is a member of Mekong River Commission.