Perhaps you should try some spelling variations:
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
truc van » truc va, thuc van, truc ban
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
so sach » so sanh, bo sach, co sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
hanh ve » hanh vi, hanh va, hanh kem
cua tre » cua te, cuu tre, cua triet
ve cau » ke cau, va cau, ve cac

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: so sach van nang xa hoi. hieu ve cau truc van hanh ve ((cua tre) OR (su triet))~.
• Adding a wildcard symbol may retrieve word variants: so sach van nang xa hoi. hieu ve cau truc van hanh ve ((cua tre) or (su triet))*.