Perhaps you should try some spelling variations:
trinh chat » tinh chat, trinh han, trinh phan
ngung cong » nhung cong, dung cong, nganh cong
hieu manh » chieu xanh, hieu nganh, dieu hanh
doc hieu » toc thieu, hoc thieu, hoc hien
cong tan » cong tac, cong san, cong thanh
phan cac » nhan cach, phan lap, phan van
phan dau » phan tu, hang dau

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 manh - hanh ((trinh chat) OR (trinh luat)) ngung cong tan ((phan cac) or (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu manh - hanh ((trinh chat) OR (trinh luat)) ngung cong tan ((phan cac) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu manh - hanh ((trinh chat) OR (trinh luat)) ngung cong tan ((phan cac) or (phan dau))".
• Adding a wildcard symbol may retrieve word variants: doc hieu manh - hanh ((trinh chat) OR (trinh luat)) ngung cong tan ((phan cac) or (phan dau))*.