Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
chieu xanh » chieu sach, chieu sang, chieu tinh
trung kha » trung khoa, truong khoa, trung khanh
dung cong » dung trong
cong doan » cong dan, cong hoan, dong doanh
trung ha » trung hoc, trung tam, trung cap
doan van » doan va, hoang van, luan 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 ((hieu nganh) or (chieu xanh)) - hanh ((trung kha) OR (trung ha)) dung cong doan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu nganh) OR (chieu xanh)) - hanh ((trung kha) OR (trung ha)) dung cong doan van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu nganh) or (chieu xanh)) - hanh ((trung kha) OR (trung ha)) dung cong doan van ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu nganh) or (chieu xanh)) - hanh ((trung kha) OR (trung ha)) dung cong doan van ban*.