天知道我多爱你地知道我多想你
[tiān zhī dào wŏ duō ài nĭ dì zhī dào wŏ duō xiăng nĭ]
The saying implies an exaggerated expression of love and longing for someone, indicating a very deep emotional state. It suggests that the depth of the affectionate and missed feelings towards a person are witnessed by heaven and earth themselves.