Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach van » sach han, sach va, bach van
su triet » su viet, su tien, ve triet
van nang » van quang, van ban, van dong
hieu va » lieu va, hieu qua
va cham » va chat, va tham
nang xa » nang x, lang xa, nang ma
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach van nang xa hoi. hieu va cham ((luc va) or (tuc va)) hanh va ((cua tre) or (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach van nang xa hoi. hieu va cham ((luc va) OR (tuc va)) hanh va ((cua tre) OR (su triet)).
• Adding a wildcard symbol may retrieve word variants: toc sach van nang xa hoi. hieu va cham ((luc va) or (tuc va)) hanh va ((cua tre) or (su triet))*.