Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thu sach » tu sach, thuat sach, thuoc sach
cham luc » cham soc, nhan luc, cham cuu
te sach » toc sach
tinh vi » trinh vi, tinh voi, tinh va
va tinh » may tinh
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua

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) or (thu sach)) ky tang xa hoi. ((hieu ve) or (hieu van)) cham luc va tinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thu sach)) ky tang xa hoi. ((hieu ve) OR (hieu van)) cham luc va tinh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thu sach)) ky tang xa hoi. ((hieu ve) or (hieu van)) cham luc va tinh vi cua tre*.