Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, nhung don
hang cong » dang cong, hang nong, bang cong
theo chu » theo chieu, cho chu, chao chu
chu xanh » chu manh, chieu xanh, chua xang
toan cao » toan tap
toan ban » van ban
anh ban » anh bang, anh bai, anh van
ban cua » ban quan

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

• If you are trying to use Boolean operators, they must be ALL CAPS: theo chu xanh - anh ban cua ((nhung cong) OR (hang cong)) trinh ((toan cao) OR (toan ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo chu xanh - anh ban cua ((nhung cong) OR (hang cong)) trinh ((toan cao) or (toan ban))~".
• Adding a wildcard symbol may retrieve word variants: theo chu xanh - anh ban cua ((nhung cong) OR (hang cong)) trinh ((toan cao) or (toan ban))*.