Perhaps you should try some spelling variations:
farmers using » barriers using, farmers union, corners using
small farmers » small firms
ying yang » yang yang, yin yang, ying chang
using dem » using dea, using dhm, using deep
yang jui » yang judy, yang di, yang yi
yu yang » du yang, yi yang, yu fang
yang xi » yang di, yang yi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ying yang) or (yu yang)) ((yang xi) OR (yang jui)) small farmers using dem bei ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ying yang) OR (yu yang)) ((yang xi) OR (yang jui)) small farmers using dem bei ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ying yang) or (yu yang)) ((yang xi) OR (yang jui)) small farmers using dem bei ;*".