The red paper-sticking custom is a cultural heritage of the San Diu people in Tuyen Quang Province.

Accordingly, families that have a peaceful year (without any death) can stick red papers. Meanwhile, families which have funerals will stick green, yellow and white papers. Their fruit trees and cattle barns are also covered with coloured paper to notify their ancestors and prevent demons from interfering or causing destruction.

Red paper is considered good luck, symbolising a prosperous new year. Blue, yellow, and white papers are supposed to express gratitude to ancestors and decedents, while hoping for a lucky new year.

The San Diu people believe that everything has a soul and the world has 3 floors (heaven, earth and the netherworld). After a year of hard work, people will relax and enjoy the Lunar New Year Festival, so the tools of labour also need to take a rest. People can work well and have a good crop in the new year.

The paper-sticking custom of the San Diu ethnic minority people in Tuyen Quang Province has existed for a long time. However, it has been preserved and passed down through many generations, contributing to solidifying their diverse national cultural identity.