家丑不可外传

jiā chǒu bù kě wài chuán lit. family shames must not be spread abroad (idiom); fig. don't wash your dirty linen in public

， 流言

liú yán rumor; gossip; to spread rumors

切莫

qiè mò you must not; Please don't...; be sure not to; on no account (do it)

轻信

qīng xìn to easily trust; gullible; naïve