Eng: Little known

曲

Bend, Bent, Bias, Biased, Crooked, Curve, Curved, Drama, Flex, Little known, Mistaken, Obscure, Play, Song, Tune, Twisted, Unjust, Unjustifiable, Verse, Wrong

深奧

Abstruse, Deep, Difficult to understand, Little known, Profound, Recondite