舞文弄墨

wǔ wén nòng mòwuwennongmo

1. (idiom) to display one's facility with words
2. to show off one's literary skills
3. (original meaning) to pervert the law by playing with legal phraseology (墨[mo4] was a reference to 繩墨|绳墨[sheng2 mo4])

Study it in Yanamino