Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh vai » thanh hai, thanh van, thanh tai
van thanh » ban thanh, van tuan
tu sach » thu sach, su sach, te sach
ve phan » va phan, ke phan, ve phat
vai cua » dai cua, hai cua, lai cua
duc van » duc va, duc tan, duc manh
ve pham » vi pham, v pham, ve phat
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet

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) or (thuoc sach)) ky nang ma hoa. hieu ((ve pham) OR (ve phan)) duc van thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky nang ma hoa. hieu ((ve pham) OR (ve phan)) duc van thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuoc sach)) ky nang ma hoa. hieu ((ve pham) OR (ve phan)) duc van thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky nang ma hoa. hieu ((ve pham) OR (ve phan)) duc van thanh vai cua tre*.