Perhaps you should try some spelling variations:
vien nganh » vien thanh
chieu xanh » chieu sach, chieu sang, chieu tinh
dung cong » dung trong
tang kha » tang ha, hang khoa, dang khai
tang khu » tai khu, tang ha, tang thi
cong dan » cong san, cong tan, huong dan
dan van » dang van, doan van, dao 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 ((vien nganh) or (chieu xanh)) - hanh ((tang kha) OR (tang khu)) dung cong dan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((vien nganh) OR (chieu xanh)) - hanh ((tang kha) OR (tang khu)) dung cong dan van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((vien nganh) or (chieu xanh)) - hanh ((tang kha) OR (tang khu)) dung cong dan van ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((vien nganh) or (chieu xanh)) - hanh ((tang kha) OR (tang khu)) dung cong dan van ban*.