Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
chieu sang » chieu sach, chieu xanh, hieu lang
hieu manh » chieu xanh, hieu nganh, dieu hanh
trinh han » trinh quan
dang cong » dung cong
han dang » phan dang, nhan dang, chan dang
cong tuc » cong thuc, cong tac, cong suc

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) or (chieu sang)) - hanh trinh han dang cong tuc ((va bao) OR (va bai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (chieu sang)) - hanh trinh han dang cong tuc ((va bao) OR (va bai)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) or (chieu sang)) - hanh trinh han dang cong tuc ((va bao) OR (va bai))".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) or (chieu sang)) - hanh trinh han dang cong tuc ((va bao) OR (va bai))*.