Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
phan dau » phan tu, hang dau
tao hoi » tao khoi, tao boi, thao hoc
tay hoi » tay ho, tay thai
sach ky » sac ky, sach y, sach ty
hieu vi » hieu voi, hieu va, hieu ve
ky sang » ky nang, ky dang, ky tang
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: toc sach ky sang ((tao hoi) OR (tay hoi)). hieu vi pham duc va ((phan lap) OR (phan dau)) cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky sang ((tao hoi) OR (tay hoi)). hieu vi pham duc va ((phan lap) or (phan dau)) cua te~".
• Adding a wildcard symbol may retrieve word variants: toc sach ky sang ((tao hoi) OR (tay hoi)). hieu vi pham duc va ((phan lap) or (phan dau)) cua te*.