好事不出门，恶事传千里

hǎo shì bù chū mén , è shì chuán qiān lǐhaoshibuchumen,eshichuanqianli

1. lit. good deeds do not go beyond the door, evil deeds spread a thousand miles
2. a good deed goes unnoticed, but scandal spreads fast (idiom)

Study it in Yanamino