Perhaps you should try some spelling variations:
vien cac » vien bach, vien da, gian cac
danh dai » danh dau, danh di, danh sai
vien dai » hien dai
va danh » va dinh, va dan, va hanh
sach ky » sac ky, sach y, sach ty
te sach » toc sach
nang xa » lang xa, nang ma, mang xa
cua te » cua tu
du va » dau va, tu va, su va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky ((nang xa) OR (nang x)) hoi. hieu ((vien cac) or (vien dai)) du va danh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (nang x)) hoi. hieu ((vien cac) OR (vien dai)) du va danh dai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang xa) OR (nang x)) hoi. hieu ((vien cac) or (vien dai)) du va danh dai cua te".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang xa) OR (nang x)) hoi. hieu ((vien cac) or (vien dai)) du va danh dai cua te*.