Perhaps you should try some spelling variations:
thien thanh » tien thanh, thi thanh, hien hanh
hien nhanh » hien hanh, tien thanh, dien thanh
thanh tung » thanh cong
trong dan » trong dang, trong tan, trong ban
trong san » trong cac, cong san, dong san
tung cua » trung cua, tuong cua, dung cua
cua dung » cua dang, cua dong, qua dung
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)) - thanh tung cua dung ((trong dan) OR (trong san)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien nhanh) OR (thien thanh)) - thanh tung cua dung ((trong dan) OR (trong san)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien nhanh) or (thien thanh)) - thanh tung cua dung ((trong dan) OR (trong san)) toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien nhanh) or (thien thanh)) - thanh tung cua dung ((trong dan) OR (trong san)) toan cao*.