Perhaps you should try some spelling variations:
hien nhanh » hien hanh, thien thanh, dien thanh
tien thanh » tien thinh, tran thanh, den thanh
thanh tung » thanh cong
dung cong » dung trong
cong lang » cong vang, cong luong, cong quang
lang nhan » bang nhan, luong nhan, hoang nhan
nhan tai » hang tai, van tai, toan tai
va dung » van dung, va duong, vat dung

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 (tien thanh)) - ((thanh trung) or (thanh tung)) va dung cong lang nhan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien nhanh) OR (tien thanh)) - ((thanh trung) OR (thanh tung)) va dung cong lang nhan tai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien nhanh) OR (tien thanh)) - ((thanh trung) or (thanh tung)) va dung cong lang nhan tai".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien nhanh) OR (tien thanh)) - ((thanh trung) or (thanh tung)) va dung cong lang nhan tai*.