Perhaps you should try some spelling variations:
thieu xanh » hieu manh, thien anh, thien danh
chieu xanh » chieu sach, chieu sang, chieu tinh
bang cong » dang cong, bang song, hang cong
tang cua » mang cua, tang luan, thong cua
hang cua » mang cua, hang ca, huong cua
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (chieu xanh)) - hanh ((tang cua) OR (hang cua)) bang cong tac toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) OR (chieu xanh)) - hanh ((tang cua) or (hang cua)) bang cong tac toan cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) OR (chieu xanh)) - hanh ((tang cua) or (hang cua)) bang cong tac toan cau*.