Possible Clues:

• Brown paintings maybe turning up in religious literature
• A Hindu or Buddhist religious text
• Mystical Hindu text
• Mystical text in Sanskrit
• Tibetan Buddhist practice
• Religious doctrine's final word about spiritual books
• Yellowish-brown paintings maybe recalled religious writings
• Eastern philosophy embraced by Tibetan travellers
• Hindu tradition that's two men's names in reverse
• Bronze sculptures perhaps turned round to reveal mystical text