Perhaps you should try some spelling variations:
luan thong » luan phong, luan tuong, luat thong
duong manh » duong van
doi chieu » doi chi, ho chieu, mot chieu
cach dung » sach dung, cach mang, tac dung
doc hieu » toc thieu, hoc thieu, hoc hien
cong tac » cong ty
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: ((doi chieu) OR (doc hieu)) xanh - cach dung luan thong ((duong manh) or (cong tac)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) xanh - cach dung luan thong ((duong manh) OR (cong tac)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doc hieu)) xanh - cach dung luan thong ((duong manh) or (cong tac)) toan cao".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (doc hieu)) xanh - cach dung luan thong ((duong manh) or (cong tac)) toan cao*.