Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hoc thieu » toc thieu, hoc hien
tong cong » trong cong, dung cong, dang cong
cong cong » cong dong, trong cong, dung cong
tac toan » tap toan, hach toan, tich toan
tam toan » tap toan, tam than, pham toan
cong cu » chung cu

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 xanh - thanh cong cu ((tong cong) OR (cong cong)) ((tac toan) or (tam toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - thanh cong cu ((tong cong) OR (cong cong)) ((tac toan) OR (tam toan)) cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - thanh cong cu ((tong cong) OR (cong cong)) ((tac toan) or (tam toan)) cau*".