Perhaps you should try some spelling variations:
cua triet » su triet, va triet
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
qua cac » cua cac
cac duc » cac du, cao duc, cac dac
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
ma hoi » mai hoi, xa hoi, me hoi

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 ty nang ((ma hoi) or (ma hoa)). hieu qua cac duc va hanh di ((cua triet) OR (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang ((ma hoi) OR (ma hoa)). hieu qua cac duc va hanh di ((cua triet) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang ((ma hoi) or (ma hoa)). hieu qua cac duc va hanh di ((cua triet) OR (cua viet))".
• Adding a wildcard symbol may retrieve word variants: te sach ty nang ((ma hoi) or (ma hoa)). hieu qua cac duc va hanh di ((cua triet) OR (cua viet))*.