Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
hanh tai » thanh tai, hang tai, han tai
hieu van » hieu va, thien van, lieu va
nang xa » lang xa, nang ma, mang xa
sach ty » sach y, sach tu, sach thu
van cam » van nam, van lam, van cau
tai cua » thai cua, tai cuc, tri cua
xac va » tac va, ac va, bac va
cua te » cua tu

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: doc sach ty ((nang xa) OR (nang x)) hoi. hieu van cam ((xac va) OR (duc va)) hanh tai cua te~.
• Adding a wildcard symbol may retrieve word variants: doc sach ty ((nang xa) or (nang x)) hoi. hieu van cam ((xac va) or (duc va)) hanh tai cua te*.