The movie is named after one of the Dong ethnic group's most famous traditional art forms, a chorus performed without the aid of musical instruments.
The songs, which range from themes as diverse as the group's history to the daily routine of their lives, were inscribed in UNESCO's list of intangible cultural heritage in 2009.
The film's director Ou Chouchou and her crew toured nearly 100 villages to interview folk song masters, collecting around 1,000 songs, around half of the group's existing total.
Twenty-four songs shortlisted from 48 are showcased in the movie, with artists from the China Philharmonic Orchestra and the National Center for the Performing Arts to add accompanying music.
Ou explains the folk songs were handled in this way to widen their appeal to a younger, contemporary audience.
"A local saying goes 'rice nourishes the body, while songs nourish the soul'. Music is part of their life and reflects their spirit. I hope their songs will be heard by more people," Ou says.
But the movie, which is based on a true story, may resonate more with young people searching for true love.
With a timeline spanning around 60 years, the movie centers on a gifted Dong singer, who wants to marry her childhood sweetheart but is instead forced to become the wife of a wealthy man. After a devastating fire claims the life of her first love, the woman suffers a breakdown and edges toward the brink of insanity. In the end, her husband's decades-long care for her finally cures her broken heart.
