gǒu​kǒu​lǐ​tǔ​bù​chū​xiàng​yá

nothing nice comes from a filthy mouth

Senses

狗口里吐不出象牙/ 狗口裡吐不出象牙 gǒu​kǒu​lǐ​tǔ​bù​chū​xiàng​yá nothing nice comes from a filthy mouth

a foul mouth cannot produce refined language; mean or vulgar people can only speak coarsely

References

variant 狗嘴里吐不出象牙/狗嘴裡吐不出象牙 狗口里吐不出象牙/狗口裡吐不出象牙