What do you mean by thinking? What is the explanation?

Yan, the abbreviation of Sanskrit yāna (Yan Na). The free translation is "ride", which means carrying and transporting, that is, the Buddha's teaching method is like the load of a car, which can help all beings enter nirvana. Four-faced refers to four times, which can also be called four-faced people. That is, (1) those who have heard the teachings of the Buddha, practiced the four truths and realized the truth. (2) Many reasons are enlightened, those who have attained Buddhism, and twelve reasons are enlightened. (3) Bodhisattva, who has made achievements in his own practice, can enlighten all beings at the same time. (4) Buddhists, besides being able to realize the Tao by themselves and others, are more successful in their practice because of their positions. [Mahayana Release Volume 1] (refer to Five Multiplies 1 126 and Four Multiplies 1743) p 1737.