Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
toc sach » hoc sach, doc sach, thuoc sach
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
su tien » su kien, su hien, tu tieng
hieu ve » hieu va, hieu van
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
ve cac » va cac, vien cac

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

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