jiā​huā​méi​yǒu​yě​huā​xiāng

extramarital attraction

家花没有野花香 (家花沒有野花香) jiā​huā​méi​yǒu​yě​huā​xiāng
extramarital attraction
A figurative idiom suggesting that men often find other women more alluring and exciting than their own wives or partners.
grass is greener
An idiomatic expression describing the general human tendency to value what is unfamiliar or external more than what one already possesses.

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Definitions
CC-CEDICT