Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
cau thuc » cau truc, cuu thuc, can thuc
dinh vi » dinh ve, dinh viet, dinh tri
nang ha » nang hai, nang han, nang hoa
cua tre » cua te, cuu tre, dua tren
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va dinh » van dinh, va kinh, va tinh
ve cau » ke cau, va cau, ve cac
ha hoi » hoa hoi, ha noi, xa hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cac) or (toc sach)) ky nang ha hoi. hieu ve cau thuc va dinh vi ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cac) OR (toc sach)) ky nang ha hoi. hieu ve cau thuc va dinh vi ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: ((tu cac) or (toc sach)) ky nang ha hoi. hieu ve cau thuc va dinh vi ((cua tre) or (cua triet))*.