Vietnamese Thiền, also known as Vietnamese Zen Buddhism, is a school of Mahayana Buddhism that originated in Vietnam and is heavily influenced by Chinese Chan Buddhism. As with other schools of Buddhism, the teachings and practices of Vietnamese Thiền are based on various texts and scriptures that are considered to be the core of its teachings.

One of the main texts used in Vietnamese Thiền is the Diamond Sutra, also known as the Vajracchedikā Prajñāpāramitā Sūtra. This text is considered to be one of the most important sutras in Mahayana Buddhism and is believed to have been translated into Vietnamese by the Indian monk Venerable Vinitaruci in the 6th century. The Diamond Sutra emphasizes the concept of emptiness and the practice of non-attachment, which are central to Vietnamese Thiền teachings.

Another important text in Vietnamese Thiền is the Lankavatara Sutra, also known as the Lankavatara Sutra. This text is believed to have been translated into Chinese by the Indian monk Gunabhadra in the 5th century and later translated into Vietnamese by the Chinese monk Venerable Thien An in the 7th century. The Lankavatara Sutra focuses on the concept of the "storehouse consciousness" and the practice of mindfulness, which are integral to Vietnamese Thiền meditation.

The Heart Sutra, also known as the Prajñāpāramitā Hṛdaya Sūtra, is another important text in Vietnamese Thiền. This short but powerful sutra is believed to have been translated into Vietnamese by the Indian monk Venerable Dharmarakṣa in the 4th century. The Heart Sutra emphasizes the concept of emptiness and the practice of compassion, which are key elements of Vietnamese Thiền teachings.

In addition to these sutras, Vietnamese Thiền also draws inspiration from the teachings of the Vietnamese Zen master Venerable Thich Nhat Hanh, who has written numerous books on the practice of mindfulness and engaged Buddhism. His teachings, which are based on traditional Vietnamese Thiền practices, have become popular around the world and have played a significant role in spreading the teachings of Vietnamese Thiền.

In conclusion, the main texts and scriptures used in Vietnamese Thiền are the Diamond Sutra, the Lankavatara Sutra, the Heart Sutra, and the teachings of Venerable Thich Nhat Hanh. These texts and teachings form the foundation of Vietnamese Thiền and guide practitioners on their path towards enlightenment and inner peace.