Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
su triet » su tien, ve triet
dinh sai » dinh tai, danh sai, dinh hai
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va dinh » van dinh, va kinh, va tinh
nang co » nang cao, nang doc, nang noi
su viet » so viet
tu sach » thu sach, su sach, te sach
co hoi » co hoc, co loi
y nang » ky nang, ly nang, v nang
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 y nang co hoi. hieu va am thuc va dinh sai ((((su triet) OR (su viet))) OR (va triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang co hoi. hieu va am thuc va dinh sai ((((su triet) OR (su viet))) or (va triet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang co hoi. hieu va am thuc va dinh sai ((((su triet) OR (su viet))) or (va triet))*.