Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach nay » sach hay, sach vay, sach nang
va triet » va thiet, va trien, ve triet
dang xay » dang van, van xay
nay dang » nam dang, nao dang, nap dang
xay hoi » xa hoi, tay hoi, cay phoi
thi van » thi lan, thi hanh, thi nang
cam luc » cam xuc, cau luc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
su viet » so viet
luc va » duc va, tuc va, loc va

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 nay dang xay hoi. ((thien van) OR (thi van)) cam luc va hanh va ((su viet) OR (va triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach nay dang xay hoi. ((thien van) OR (thi van)) cam luc va hanh va ((su viet) or (va triet))~".
• Adding a wildcard symbol may retrieve word variants: toc sach nay dang xay hoi. ((thien van) OR (thi van)) cam luc va hanh va ((su viet) or (va triet))*.