dredge the moon out from the bottom of the water
As a Chinese idiom, the Pinyin is Shu ǐ D ǐ L ā oyu è, which means that you can only waste your efforts to do something you can't do at all. From chuanxilu.
The origin of Idioms
Wang Shouren's chuanxilu of Ming Dynasty says: "if you want to seek the sound of yuan in the grain of Jiahui millet, it's like fishing for the moon at the bottom of the water."
Idiom usage
In vain; in vain.
dredge the moon out from the bottom of the water
Thousands of miles of marriage leads the line - qiān lǐ yīn yuán shǐ xiàn qiān
communication between minds with loving glances - sè shòu hún yǔ