Perhaps you should try some spelling variations:
dong zhang » dong hoang, dong sheng, dong yang
human gene » human genome, human gender, human bone
zhang yan » zhang fan, zhang jian, wang yan
hua gene » a gene, hua ren, hy5 gene
yan thi » tran thi, dang thi, nhan thi
yan zhi » yan zi, wang zhi
hong yu » wong yue

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

• Performing a fuzzy search may retrieve terms with similar spellings: dong zhang yan ((hua gene) or (human gene)) ((yan thi) OR (yan zhi)) hong yu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: dong zhang yan ((hua gene) OR (human gene)) ((yan thi) OR (yan zhi)) hong yu ;*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dong zhang yan ((hua gene) or (human gene)) ((yan thi) OR (yan zhi)) hong yu ;*".