弱水三千，只取一瓢飲

Etymology
From: Chapter 91 of the Dream of the Red Chamber
 * Literally: (although) the Ruo River is three thousand li long, one only drinks one ladle worth of water from it.
 * Later on, this phrase was used as a metaphor for choosing only one companion out of all potential mates.

Idiom

 * 1) there are so many potential lovers to choose from, but you only pick one from among those potential lovers