Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
chiet tach » chieu sach
thong cong » trong cong, tong cong, thong thong
hieu manh » chieu xanh, hieu nganh, hien hanh
trinh va » trinh van, trinh vat, trinh ve
va thong » va thuong, va phuong, he thong
cong san » cong tac
san than » sang than, san thanh, ban than
than tap » toan tap, han tap, phan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((((hieu manh) OR (dieu hanh))) OR (chiet tach)) - hanh trinh va thong cong san than tap~.
• Adding a wildcard symbol may retrieve word variants: ho ((((hieu manh) or (dieu hanh))) or (chiet tach)) - hanh trinh va thong cong san than tap*.