Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
phung cong » nhung cong, phong cong, nhung chong
hoc thieu » toc thieu, hoc hien
hung cong » nhung cong, hung cuong, dung cong
tac dung » sach dung, xay dung, tin dung
san phan » san pham, van phan, sat phan
phan dau » phan tu, hang dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc thieu) or (theo chieu)) xanh - tac dung luan ((hung cong) OR (phung cong)) san phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thieu) OR (theo chieu)) xanh - tac dung luan ((hung cong) OR (phung cong)) san phan dau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thieu) or (theo chieu)) xanh - tac dung luan ((hung cong) OR (phung cong)) san phan dau".
• Adding a wildcard symbol may retrieve word variants: ((hoc thieu) or (theo chieu)) xanh - tac dung luan ((hung cong) OR (phung cong)) san phan dau*.