Perhaps you should try some spelling variations:
human gene » human genome, human gender, human bone
using dna » using dea, using data, using drag
than hong » tan hong, thang long, than one
hua gene » a gene, hua ren, hy5 gene
yan than » van thanh, yan zhang, yan clan
hong shu » cong shu, tong shui, wong shiu
using a » using _

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doom ((using dna) OR (using a)) ((hua gene) OR (human gene)) yan than hong shu ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doom ((using dna) or (using a)) ((hua gene) OR (human gene)) yan than hong shu ;~".
• Adding a wildcard symbol may retrieve word variants: doom ((using dna) or (using a)) ((hua gene) OR (human gene)) yan than hong shu ;*.