我有秘密那也只能是自己瞒
[wŏ yŏu mì mì nèi yĕ zhĭ néng shì zì jĭ mán]
'If I have a secret, I can only keep it to myself.' This conveys the idea of someone being very secretive or unable to share their true feelings with others, perhaps due to trust issues or personal reasons.