India is the birthplace of yoga. Since Upanishads era, yoga has almost become an unavoidable topic in Indian religious philosophy classics. The Bhagavad-gita is a book compatible with philosophy, religion and yoga practice.

There are many such sentences in the Upanishads, but they look very laborious.

There are yoga sutras, which I haven't seen.

In China, an Indian tutor, Sagulu, started Isayuga, and its Sina blog post is particularly good.

There is also Perfect Health written by American Indian Deepak chopra, which mainly introduces Indian medicine and also includes some yoga methods (mainly not yoga).

Mary Bear Stearns's Yoga: Meditation and Practice of Body and Mind also introduces meditation and pranayama, but there are too many psychological elements in it. The examples cited are also family breakdown, self-redemption, childhood shadows, and feelings are mainly not meditation and pranayama.

The above contents are for reference only.