Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
quan nhung » qua nhung, cua nhung, luan chung
hien xanh » hien hanh, hien nhanh, chieu xanh
canh ban » can ban, canh dan, canh van
cong san » cong tac
toan cao » toan tap
toan ban » van ban
can van » cac van, can ban, tan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien xanh - ((canh ban) or (can van)) quan nhung cong san ((toan cao) OR (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - ((canh ban) OR (can van)) quan nhung cong san ((toan cao) OR (toan ban)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - ((canh ban) or (can van)) quan nhung cong san ((toan cao) OR (toan ban))".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - ((canh ban) or (can van)) quan nhung cong san ((toan cao) OR (toan ban))*.