Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
trinh van » trinh quan, trinh toan, dinh van
trinh han » trinh quan
hang cong » dang cong, hang nong, bang cong
chinh cau » chinh chau, chinh ca, chinh can
hoc hieu » hoc thieu, hoc hien, doc hieu
cong dan » cong san, cong tan, huong dan
chan cau » phan cau, can cau, nhanh cau

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 manh - canh ((trinh van) or (trinh han)) hang cong dan ((chan cau) or (chinh cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - canh ((trinh van) OR (trinh han)) hang cong dan ((chan cau) OR (chinh cau)).
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - canh ((trinh van) or (trinh han)) hang cong dan ((chan cau) or (chinh cau))*.