as for the moon 幻想得到无法得到的东西

ask/ cry for the moon

幻想得到无法得到的东西；想做做不到的事。

to ask for something that is difficult or impossible to get or achieve

例句：

Wanting a decent job and a home is hardly asking for the moon.

想要一份体面的工作和一个家并不是什么奢望。