“花力气不讨好”用英语怎么说?

是"吃力不讨好"吗?
以下翻译供你参考,要看语境使用:
work hard but get little result;thankless;a thankless task; arduous but fruitless; be a fool for one's pains; do a hard but thankless job; look for a needle in a bundle of hay
例句: If you try to help him, you will be a fool for your pains.
要是你想帮助他这个人， 那将是吃力不讨好。

a waste of time

Effort not to please.