Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh dai » hanh tai, hanh dao, vanh dai
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
tai hoe » tai he, tai khoa, thai hoc
dai hoi » dai hoc, dai hai, dai moi
hieu va » lieu va, hieu qua
cac luc » cau luc, coc luc, cac nuoc
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, dua tren
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky nang ((tai hoe) or (dai hoi)). hieu va cac luc va hanh dai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang ((tai hoe) OR (dai hoi)). hieu va cac luc va hanh dai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang ((tai hoe) or (dai hoi)). hieu va cac luc va hanh dai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang ((tai hoe) or (dai hoi)). hieu va cac luc va hanh dai ((cua tre) OR (cua triet))*.