Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi hanh » thi thanh
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
te sach » toc sach
hanh co » anh co, danh co, hanh mo
van cac » van hac, van cau, van bac
cua cau » cua cac, cua cay, cua cu
cua can » cua cac, cua ban, cua dan
cua chu » sua chua
cac vu » cac du, cac vi, cac tu
vu ban » tu ban, va ban

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach thi hanh co hoc. hieu van cac vu ban hanh vi ((((cua cau) OR (cua can))) OR (cua chu))~.
• Adding a wildcard symbol may retrieve word variants: te sach thi hanh co hoc. hieu van cac vu ban hanh vi ((((cua cau) or (cua can))) or (cua chu))*.