It is estimated that the villages of Cham ethnic people in central Viet Nam are preserving around 60,000 ancient documents that remain mostly unknown to the world.
Most of these documents are written in Sanskrit on buong, the leaves of a type of palm tree that grows in central Viet Nam. Sanskrit is an ancient Hindu and classical literary language of India now lost to today's Cham people.
However, one Cham teacher is determined to unlock his people's secrets. Tinh has mastered Sanskrit to decipher the Mystery of the Leaves and as a teacher, has free access to the ancient documents considered by the Cham as something akin to a family heirloom.
Tinh has discovered the leaves contain a treasure of tales, legends, historic events, poems, songs and rituals. "They are handed down from generations to generations," explains Tinh.
"People keep them with great care without knowing entirely their meaning. If some documents happened to decay, people will cast the dust into nature. That is why it is not easy to collect these buong leaf documents."
The young buong leaf was first cut in equal lengths and then dried for one day under the sun. The Cham people used a sharp stick to write on them.
When they finished, they coated some unknown powder on the leaves to make the writings indelible. A buong leaf can hold four lines of Sanskrit.
Tinh has thousands of these ancient and mysterious Cham documents, some in their original condition, some copied by him.
He says, "It's a great honour for me to shed some light into the Chams' fabulous spiritual heritage."