Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, thien anh, thien danh
hieu manh » chieu xanh, hieu nganh, dieu hanh
cang tang » cang thang, cong tang, lang thang
dung cong » dung trong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cau » toan cao, toan ban, toan tap
tang cu » tang cua, tang ca, tang co
cu dung » su dung, cau duong, duc dung

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) or (hieu manh)) - cang tang cu dung cong tap toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (hieu manh)) - cang tang cu dung cong tap toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (hieu manh)) - cang tang cu dung cong tap toan cau*.