Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
thanh tung » thanh cong
hoc thieu » toc thieu, hoc hien
chua dong » cua dong, ha dong, huy dong
dong cong » duong cong, dung cong, dang cong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap

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 trung) or (thanh tung)) chua dong cong tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - ((thanh trung) OR (thanh tung)) chua dong cong tap toan cao*.