Perhaps you should try some spelling variations:
tranh trong » tran trong, trinh trong, anh trong
thanh trong » thanh trung, hanh trong, nhanh trong
phap thong » phap phong, phap chong, pho thong
hiem ngan » kim ngan, viem gan
hoc hiem » hoc hien, hoc thieu, hoc thiet
cong san » cong tac
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hiem ngan - ((thanh trong) OR (tranh trong)) phap thong ((cong san) or (huong dan)) than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hiem ngan - ((thanh trong) OR (tranh trong)) phap thong ((cong san) OR (huong dan)) than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hiem ngan - ((thanh trong) OR (tranh trong)) phap thong ((cong san) or (huong dan)) than cau".
• Adding a wildcard symbol may retrieve word variants: hoc hiem ngan - ((thanh trong) OR (tranh trong)) phap thong ((cong san) or (huong dan)) than cau*.