Is Tian Shu an idiom?

"Heaven comb" is not an idiom, but there is only one idiom containing "Heaven":

A good living environment is like being in heaven.

Dingdong dingdong

Explaining and describing the beauty of the living environment is like being in a heavenly palace.

Song Yuanzhang's "Maple Window" Source: "In the middle of the year, Yuhang is full of things and the ground is full."

Formal idioms

This usage is formal; Become an object; Metaphor life is rich and colorful.

Synonym fairyland on earth

For example, the Song Dynasty's "Qing Geography": "Rich and Han, Yuhang is the best, everything is prosperous, and it is also a paradise on the earth."