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
cong san » cong tac
chang tu » chung tu, hang tu, thang tu
chang xu » chang xue, chao xu, thong xu
manh va » anh va, minh va, lanh va
hanh va » hang va, hanh vi

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 - canh ((manh va) or (hanh va)) nhung cong san ((chang tu) OR (chang xu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - canh ((manh va) OR (hanh va)) nhung cong san ((chang tu) OR (chang xu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - canh ((manh va) or (hanh va)) nhung cong san ((chang tu) OR (chang xu))".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh ((manh va) or (hanh va)) nhung cong san ((chang tu) OR (chang xu))*.