Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
hanh lai » hanh lam, hanh tai, thanh lap
tang van » dang van, hoang van, trong van
tu sach » thu sach, su sach, te sach
lai cua » dai cua, hai cua, lai chau
van cau » van dau, van hau, van chat
ky tang » ky nang, ky dang, kho tang
van hoc » van hoa
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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 tang van hoc. hieu van cau ((xuc va) OR (tuc va)) hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky tang van hoc. hieu van cau ((xuc va) OR (tuc va)) hanh lai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuoc sach)) ky tang van hoc. hieu van cau ((xuc va) OR (tuc va)) hanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky tang van hoc. hieu van cau ((xuc va) OR (tuc va)) hanh lai cua tre*.