画鬼容易画人难

画鬼容易画人难

Literally means:

it's easier to draw a picture of the ghost than of a man

Actually means:

Since demons or ghosts do not really exist, no matter how you picture them, people cannot find fault with such pictures. By contrast, man with his natural existence known to all is not easily pictured any flaw with your picture will be easily discerned.

It figuratively means that things unfamiliar to people can be easily feigned while the more familiar a thing is, the more difficult it is to describe or picture.

鬼怪是不存在的，你想怎么画就怎么画，别人不可能批评你画错了或画得不好，所以画鬼很容易；而人是现实存在的，大家都知道的，你画的人只要有点小毛病，别人就可以看出来，所以要把人画好是不容易的。

比喻人们越陌生的事物越容易编造，人们越熟悉的事物越难以描写或刻画。