Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
danh hai » dang hai, lanh hai, manh hai
thuc day » thuc vat
thuc dan » thuc hanh, hoc dan, thuc vat
sach ky » sac ky, sach ty, sach kem
hai cua » thai cua, dai cua, hoi cua
hieu va » lieu va, hieu qua
nang co » nang cao, nang doc, nang noi
co hoi » co hoc, co loi
va am » va lam, va cam

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang co hoi. hieu va am ((thuc dan) OR (thuc day)) danh hai cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach y)) nang co hoi. hieu va am ((thuc dan) or (thuc day)) danh hai cua triet~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sach y)) nang co hoi. hieu va am ((thuc dan) or (thuc day)) danh hai cua triet*.