鱼与熊掌不可兼得

yú yǔ xióng zhǎng bù kě jiān dé
 

Meaning:

You can't have both fish and bear's paw: In order to get something, you have to sacrifice something else.

鱼 meaning fish, Fish in China is so important symbol. A fish dish is an indispensible part of every Chinese family’s New Year’s Eve feast. In China, fish and fortune are finely intertwined.
与 meaning and.
熊掌 meaning bear's paw. It`s a high-grade food in the past, and now usually means precious wealth.
不可 meaning can`t.
兼得 meaning get them both.

You must choose one or the other.
You can't always get everything you want.
You can't have your cake and eat it.
You cannot sell the cow and drink the milk.
You cannot burn the candle at both ends.