Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh lai » hanh lam, hanh tai, thanh lap
dang xay » dang van, van xay
lai cua » dai cua, hai cua, lai chau
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
luc va » duc va, loc 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: thu sach y ((nang x) or (dang xay)) hoi. hieu va cam ((luc va) or (tuc va)) hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((nang x) OR (dang xay)) hoi. hieu va cam ((luc va) OR (tuc va)) hanh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: thu sach y ((nang x) or (dang xay)) hoi. hieu va cam ((luc va) or (tuc va)) hanh lai cua tre*.