Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu xanh » chieu xanh, hieu manh, hieu nganh
doc hieu » toc thieu, hoc thieu, hoc hien
trang va » tran van, hang va
cong dan » cong san, cong tan, huong dan
dan chan » dan gian, dan ca, van chat
chan cau » phan cau, can cau, chinh cau
lan van » lang van, tan van, san van
luan » quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu xanh - hanh ((trang va) or (((lan van) OR (luan van)))) nhung cong dan chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - hanh ((trang va) OR (((lan van) OR (luan van)))) nhung cong dan chan cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - hanh ((trang va) or (((lan van) OR (luan van)))) nhung cong dan chan cau*".