Perhaps you should try some spelling variations:
nhung duong » nhung dung, nhung huong, nhung tuong
thieu khang » chieu khong, thieu quang
hieu lang » chieu sang, hieu quang, nhieu tang
tranh vat » trinh vat, tranh va, tranh van
vat nhung » va nhung, vap nhung, vai nhung
duong van » duong va, luong va, dang van
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu khang) or (hieu lang)) - canh tranh vat nhung duong van ((toan tap) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu khang) OR (hieu lang)) - canh tranh vat nhung duong van ((toan tap) OR (toan ban))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu khang) or (hieu lang)) - canh tranh vat nhung duong van ((toan tap) OR (toan ban))*".