jīng yì qiú jīng
to perfect sth that is already outstanding (idiom); constantly improving
Wǔ Jīng
the Five Classics of Confucianism, namely: the Book of Songs 詩經|诗经[Shī Jīng], the Book of History 書經|书经[Shū Jīng], the Classic of Rites 禮記|礼记[Lǐ Jì], the Book of Changes 易經|易经[Yì Jīng], and the Spring and Autumn Annals 春秋[Chūn Qīu]