Perhaps you should try some spelling variations:
thuong luong » theo luong, cong luong, thong thuong
thuong duong » tuong duong, chuong duong, thong duong
hieu quan » hieu qua, lieu quan, thien quan
manh toan » thanh toan, anh tuan, tinh toan
hoc hieu » hoc thieu, hoc hien, doc hieu
tranh va » tranh van, trinh va, thanh va
trang va » tran van, hang va
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu quan - canh ((tranh va) OR (trang va)) ((thuong duong) or (thuong luong)) manh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu quan - canh ((tranh va) OR (trang va)) ((thuong duong) OR (thuong luong)) manh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu quan - canh ((tranh va) OR (trang va)) ((thuong duong) or (thuong luong)) manh toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc hieu quan - canh ((tranh va) OR (trang va)) ((thuong duong) or (thuong luong)) manh toan ban*.