An empty; Wasted Effort

Bamboo Basket Strikes Water - An Empty, Idioms, Also Do To Strike water with a bamboo basket is used as a metaphor for a wasted effort with no effect, a labor of no avail.

Bamboo basket strikes water in vain

Basic Explanation: a metaphor for effort with no effect

Separate Explanation

Bamboo basket strikes water : a metaphor for wasted effort, no effect, and labor without merit.

All in vain : 1. All hopes and efforts are lost.