Perhaps you should try some spelling variations:
thanh dung » thanh duong, thanh tung, thanh hung
khong cong » thong cong, khong cang, chong cong
bang thanh » ban thanh, dang thanh, tang thanh
hoc thiet » hoc thieu, hoc thuyet, toc thieu
hoc khong » hoa khong, hoc hong, khoi khong
bang than » ban than, sang than, bang nhan
dung hoc » dong hoc, dung thuoc, trung hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc hien) or (hoc thiet)) danh - thanh dung hoc khong cong ((bang than) or (bang thanh)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc hien) OR (hoc thiet)) danh - thanh dung hoc khong cong ((bang than) OR (bang thanh)) cau.
• Adding a wildcard symbol may retrieve word variants: ((hoc hien) or (hoc thiet)) danh - thanh dung hoc khong cong ((bang than) or (bang thanh)) cau*.