Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, tu cach
vai cua » dai cua, hai cua, lai cua
va hanh » va thanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
te sach » toc sach
cac lo » cac lop, cac co, cac bo
ve cac » va cac, vien cac

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

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