What do all the meanings of "high tunes and low numbers", "wonderful writing", "Yangchunbaixue", "writing", "extraordinary" and "unique" mean?

The high and the low - the tune is high and the people who can sing along with it are few. The old meaning is that it is hard to get a good friend. Now the metaphor is that the words or works are not popular and few people can understand them.

Mythical writing - a metaphor for outstanding writing talent.

Yangchunbaixue--originally refers to a kind of higher-ranking song of Chu in the Warring States period. It is a metaphor for high and profound unpopular literary art.

Stroke of the Dragon and Snake - describes vivid and vigorous calligraphy.

Unusual sound - mortal sound: ordinary music. Describe things as extraordinary and outstanding.

Distinctive - Don't: Another. Another unique style.