Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
vai cua » dai cua, hai cua, lai cua
anh vai » anh va, anh bai, anh van
cau luc » cau truc, cau phuc
hieu ve » hieu va, hieu van
ly nang » ky nang, ly hang, ly vang
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (thuoc sach)) ly nang ma hoi. hieu ve ((cau luc) or (cam xuc)) tuan anh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) ly nang ma hoi. hieu ve ((cau luc) OR (cam xuc)) tuan anh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) ly nang ma hoi. hieu ve ((cau luc) or (cam xuc)) tuan anh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) ly nang ma hoi. hieu ve ((cau luc) or (cam xuc)) tuan anh vai cua tre*.