Perhaps you should try some spelling variations:
among african » among africans, among american, among mexican
human gender » bhutan gender, german gender, human genome
human gene » human genome, human bone, human genetic
zong shu » cong shu, tong shui, wong shiu
dong di » dong sin
yang li » yang lin, yang di, yang xi
li zong » lin zong, li cong, li rong

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((dong di) or (among african)) ya ((human gene) OR (human gender)) yang li zong shu ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((dong di) OR (among african)) ya ((human gene) OR (human gender)) yang li zong shu ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((dong di) or (among african)) ya ((human gene) OR (human gender)) yang li zong shu ;".
• Adding a wildcard symbol may retrieve word variants: ((dong di) or (among african)) ya ((human gene) OR (human gender)) yang li zong shu ;*.