Perhaps you should try some spelling variations:
toc sach » hoc sach, thuoc sach, nuoc sach
tay lang » tai lang, tay tang, tay quang
van hanh » van thanh, ban hanh, van anh
va triet » va thiet, va trien, ve triet
doc sach » hoc sach, nuoc sach, dac sac
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
cam luc » cam xuc, cau luc
luc van » luoc van, luu van, duc van
hanh va » hang va, hanh vi
su viet » so viet
va cam » va cham, va cac, va cao

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