Perhaps you should try some spelling variations:
truong trung » tieng trung
duong thanh » dong thanh, muong thanh, luong thanh
hoc thieu » toc thieu, hoc hien
manh tung » manh hung, thanh tung
ho chieu » theo chieu, doi chieu, mot chieu
tung tac » tuong tac, ung tac, trung tam
tac dung » sach dung, xay dung, tin dung
toan tap » toan ban

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) OR (hoc thieu)) tinh - manh tung tac dung ((duong thanh) or (truong trung)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) tinh - manh tung tac dung ((duong thanh) OR (truong trung)) toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (hoc thieu)) tinh - manh tung tac dung ((duong thanh) or (truong trung)) toan tap".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (hoc thieu)) tinh - manh tung tac dung ((duong thanh) or (truong trung)) toan tap*.