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 » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
cam luc » cam xuc, cau luc
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
cua tre » cua te, cuu tre, cua triet
sach v » sach va, sach y, sach 2
luc va » duc va, tuc va, loc va
va cam » va cham, va cac, va cao

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) OR (nang x)) hoi. hieu va cam luc 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) OR (nang x)) hoi. hieu va cam luc 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) OR (nang x)) hoi. hieu va cam luc va hanh va ((cua tre) or (su triet))".
• Adding a wildcard symbol may retrieve word variants: toc sach v ((nang xa) OR (nang x)) hoi. hieu va cam luc va hanh va ((cua tre) or (su triet))*.