Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
van chao » van chat, van hao, van cho
van dinh » van minh, van dich, va dinh
tu sach » su sach, te sach, tu cach
nang xa » nang x, lang xa, nang ma
va tinh » may tinh
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua

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 (thu sach)) ky nang xa hoi. hieu van chao xu ((va tinh) or (van dinh)) va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu van chao xu ((va tinh) OR (van dinh)) va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang xa hoi. hieu van chao xu ((va tinh) or (van dinh)) va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) ky nang xa hoi. hieu van chao xu ((va tinh) or (van dinh)) va cua tre*.