Perhaps you should try some spelling variations:
dau triet » cau triet, dau tien, dau tren
su triet » su viet, su tien, ve triet
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
van cao » van dao, van hao, van cau
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
van bao » van ban, van dao

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

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