Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
so nganh » so ngan, hoc nganh, moi nganh
nang xa » lang xa, nang ma, mang xa
va hanh » va thanh, va danh, ban hanh
van cau » van dau, van hau, van chat
cau du » cau do, cac du, cau tu
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: so nganh y ((nang xa) OR (nang x)) hoi. hieu van cau du ((van hanh) or (va hanh)) vi cau triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so nganh y ((nang xa) OR (nang x)) hoi. hieu van cau du ((van hanh) OR (va hanh)) vi cau triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so nganh y ((nang xa) OR (nang x)) hoi. hieu van cau du ((van hanh) or (va hanh)) vi cau triet".
• Adding a wildcard symbol may retrieve word variants: so nganh y ((nang xa) OR (nang x)) hoi. hieu van cau du ((van hanh) or (va hanh)) vi cau triet*.