Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van dinh » van minh, van dich, xuan dinh
va dinh » va kinh, va tinh, vu dinh
cham xu » chao xu, cham cuu, chat xuc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua
x hoi » xa hoi, o hoi, x ho

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