不要把你的善良让狗看见
[bù yào bă nĭ de shàn liáng ràng gŏu kàn jiàn]
'Don't let your kindness be seen by a dog.' This implies not showing kindness to someone ungrateful or untrustworthy, like 'not casting pearls before swine', which warns people against giving good things (kindness, etc.) to someone unworthy.