Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hiem ngan » kim ngan, viem gan
tang luan » dung luan
hoc hiem » hoc hien, hoc thieu, hoc thiet
tang cua » mang cua, hang cua, thong cua
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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 - hanh ((tang cua) OR (tang luan)) nhung cong ((van toan) or (van tuan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hiem ngan - hanh ((tang cua) OR (tang luan)) nhung cong ((van toan) OR (van tuan)) ban*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hiem ngan - hanh ((tang cua) OR (tang luan)) nhung cong ((van toan) or (van tuan)) ban*".