Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
thanh ve » hanh ve, thanh va, thanh vien
va thanh » gia thanh, ban thanh, va tinh
cua tre » cua te, cua triet, dua tren
thuc va » thuc vat, thuc dan, thuc day
cuu tre » cau tren, cau treo
hieu ve » hieu va, hieu van
cao hoc » co hoc, cho hoc, chat hoc
cao hoi » cau hoi, co hoi, tao hoi
ve nam » he nam, va nam, le nam
cai ky » cao ky, cac ky, cam ky
tu cai » tu cac, tu can, tu bai

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 cai ky nang ((cao hoi) OR (cao hoc)). hieu ve nam thuc va thanh ve ((cua tre) OR (cuu tre))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cai ky nang ((cao hoi) or (cao hoc)). hieu ve nam thuc va thanh ve ((cua tre) OR (cuu tre))~".
• Adding a wildcard symbol may retrieve word variants: tu cai ky nang ((cao hoi) or (cao hoc)). hieu ve nam thuc va thanh ve ((cua tre) OR (cuu tre))*.