吃别人嚼过的馍不香
chī​bié​rén​jiáo​guò​de​mó​bù​xiāng

lack of originality

吃别人嚼过的馍不香 (吃別人嚼過的饃不香) chī​bié​rén​jiáo​guò​de​mó​bù​xiāng
lack of originality
lit. bread previously chewed by someone has no flavor; fig. there's no joy in discovering or doing something if someone else has done it first, emphasizing the value of original work.

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