Perhaps you should try some spelling variations:
thien thanh » tien thanh, thi thanh, hien hanh
thieu xanh » chieu xanh, hieu manh, thien anh
tong tuong » trong tuong, tuong tuong, tong thuong
tuong dan » huong dan, tung dan, xuong dan
tinh cua » trinh cua, sinh cua, tranh cua
dan toan » van toan, dan than, manh 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) or (thien thanh)) - hanh ((tinh cua) OR (tinh chat)) tong tuong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (thien thanh)) - hanh ((tinh cua) OR (tinh chat)) tong tuong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) or (thien thanh)) - hanh ((tinh cua) OR (tinh chat)) tong tuong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (thien thanh)) - hanh ((tinh cua) OR (tinh chat)) tong tuong dan toan cau*.