Perhaps you should try some spelling variations:
nganh xay » nganh mac, nganh y, nganh ma
van hanh » van thanh, ban hanh, van anh
vinh cuu » dinh cuu, sinh cua, dinh cu
hieu van » hieu va, thien van, lieu va
nganh ky » nganh y, hanh ky, nganh co
va danh » va dinh, va dan, va hanh
van cac » van hac, van cau, van bac
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo

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 ky) OR (nganh xay)) nang xa hoi. hieu van cac du ((van hanh) or (va danh)) vinh cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((nganh ky) OR (nganh xay)) nang xa hoi. hieu van cac du ((van hanh) OR (va danh)) vinh cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((nganh ky) OR (nganh xay)) nang xa hoi. hieu van cac du ((van hanh) or (va danh)) vinh cuu tre".
• Adding a wildcard symbol may retrieve word variants: so ((nganh ky) OR (nganh xay)) nang xa hoi. hieu van cac du ((van hanh) or (va danh)) vinh cuu tre*.