Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
trinh quan » tinh quang, trinh luat
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
hang cong » dang cong, hang nong, bang cong
tan toan » tan tran, tap toan, van toan
toan cau » 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 - canh ((trinh quan) OR (trinh han)) ((thong cong) or (hang cong)) tan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - canh ((trinh quan) OR (trinh han)) ((thong cong) OR (hang cong)) tan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - canh ((trinh quan) OR (trinh han)) ((thong cong) or (hang cong)) tan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - canh ((trinh quan) OR (trinh han)) ((thong cong) or (hang cong)) tan toan cau*.