Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
su triet » su viet, su tien, ve triet
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va cham » va chat, va tham
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang
luc va » duc va, loc va
sach v » sach va, sach y, sach 2
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 v 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 v nang xa hoi. hieu va cham ((luc va) OR (tuc va)) hanh va ((cua tre) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach v 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 v nang xa hoi. hieu va cham ((luc va) OR (tuc va)) hanh va ((cua tre) or (su triet))*.