Perhaps you should try some spelling variations:
trung va » truong va, trang va, trung ha
van nang » van quang, van ban, van dong
su triet » su viet, ve triet
sach van » sach han, sach va, bach van
su sach » so sach, vu sach
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
su tien » su kien, su hien, tu tieng
nang xa » nang x, lang xa, nang ma
ve nam » va nam, le nam, te nam
he nam » ha nam, nghe nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach van nang xa hoi. hieu ((ve nam) OR (he nam)) trung va hanh va ((su triet) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach van nang xa hoi. hieu ((ve nam) OR (he nam)) trung va hanh va ((su triet) OR (su tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach van nang xa hoi. hieu ((ve nam) OR (he nam)) trung va hanh va ((su triet) or (su tien))".
• Adding a wildcard symbol may retrieve word variants: su sach van nang xa hoi. hieu ((ve nam) OR (he nam)) trung va hanh va ((su triet) or (su tien))*.