Perhaps you should try some spelling variations:
known about » know about
yang guang » yang yang, yang liang
huang jing » huang ting, huang ying, wang jing
jing known » king know
li zhang » _ zhang
yan guan » gan guan, yan yuan, yihan guan
d huang » dr huang, 16 huang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: li zhang ((yang guang) or (yan guan)) d huang jing known about ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: li zhang ((yang guang) OR (yan guan)) d huang jing known about ;*.