Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
lam thuc » lam thuoc, am thuc, nam thuc
cua tre » cua te, cuu tre, dua tren
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
ky tang » ky nang, kho tang, ky trong
ky dang » ky nang, ky danh
va lam » van lam, va lap

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) or (ky tang)) xa hoi. hieu va lam thuc va hanh di ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky dang) OR (ky tang)) xa hoi. hieu va lam thuc va hanh di ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky dang) or (ky tang)) xa hoi. hieu va lam thuc va hanh di ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky dang) or (ky tang)) xa hoi. hieu va lam thuc va hanh di ((cua tre) OR (cua triet))*.