Perhaps you should try some spelling variations:
thien thanh » tien thanh, thi thanh, hien hanh
hien nhanh » hien hanh, tien thanh, dien thanh
trinh vant » trinh vat, trinh han, trinh viet
nhung cong » dung cong, thong cong, hang cong
trinh van » trinh han, trinh quan, trinh toan
cong dan » cong san, cong tan, huong dan
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 ((hien nhanh) OR (thien thanh)) - canh ((trinh van) or (trinh vant)) nhung cong dan toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien nhanh) OR (thien thanh)) - canh ((trinh van) OR (trinh vant)) nhung cong dan toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien nhanh) OR (thien thanh)) - canh ((trinh van) or (trinh vant)) nhung cong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien nhanh) OR (thien thanh)) - canh ((trinh van) or (trinh vant)) nhung cong dan toan cau*.