Perhaps you should try some spelling variations:
su sach » so sach, vu sach
dinh va » dinh van, dinh ve, tinh va
va dinh » van dinh, va kinh, va tinh
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
nang xa » nang x, lang xa, nang ma
te sach » toc sach
va cua » va chua, via cua, ca cua
xu va » xu van, 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: ((su sach) or (te sach)) ky nang xa hoi. ((hieu ve) OR (hieu va)) chao xu va dinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (te sach)) ky nang xa hoi. ((hieu ve) OR (hieu va)) chao xu va dinh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (te sach)) ky nang xa hoi. ((hieu ve) OR (hieu va)) chao xu va dinh va cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (te sach)) ky nang xa hoi. ((hieu ve) OR (hieu va)) chao xu va dinh va cua tre*.