Perhaps you should try some spelling variations:
sach thuc » cach thuc, sach thu, sach thue
thu sach » tu sach, thuat sach, thuoc sach
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
va chat » van chat, va phat, cao chat
cua tre » cua te, cuu tre, cua triet
vu cham » va cham, vu kham, tu cham
luc va » duc va, tuc va, loc va
ca hoi » cau hoi, cua hoi, co hoi
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: thu sach thuc hanh ((ca hoi) or (xa hoi)). hieu ((vu cham) or (va chat)) luc va tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach thuc hanh ((ca hoi) OR (xa hoi)). hieu ((vu cham) OR (va chat)) luc va tinh va cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach thuc hanh ((ca hoi) or (xa hoi)). hieu ((vu cham) or (va chat)) luc va tinh va cua tre*.