【方言】snarl and snap at Lü Dongbin(one of the eight immortals in Chinese mythology )—wrong a kind-hearted person
狗咬呂洞賓，不識好人心
like the dog that bit Lü Dongbin,you bite the hand that feeds you—mistake a good man for bad one
狗咬呂洞賓，不識好人心ɡǒu yǎo lǚ dònɡ bīnɡ ,bù shí hǎo rén xīn
狗咬了常做善事的呂洞賓。比喻不識好和壞。mistake a good man for a bad one, wrong a kind hearted person