Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cua triet » cua viet, su triet, va triet
day thanh » dao thanh, dat thanh, da thanh
thuc day » thuc dan, thuc vat
thanh va » thanh van, hanh va, thanh ha
tu sach » thu sach, su sach, te sach
vi tham » vi pham, va tham, vi than
hieu vi » hieu voi, hieu va, hieu ve
cao hoi » cau hoi, cao hoc, tao hoi
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
co hoi » co hoc, co loi

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 y nang ((cao hoi) or (co hoi)). hieu vi tham thuc day thanh va ((cua triet) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((cao hoi) OR (co hoi)). hieu vi tham thuc day thanh va ((cua triet) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((cao hoi) or (co hoi)). hieu vi tham thuc day thanh va ((cua triet) or (cuu tre))*.