Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cham thuc » nham thuc, pham thuc, tham thuc
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
tu sach » thu sach, su sach, te sach
hieu ve » hieu van
nang ma » tang ma, sang ma, nang cao
hoc anh » hoc nganh, hoc nhanh, ngoc anh
vi cua » vai cua, di cua

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) or (hoc anh)) ky nang ma hoa. ((hieu ve) OR (hieu va)) cham thuc va hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (hoc anh)) ky nang ma hoa. ((hieu ve) OR (hieu va)) cham thuc va hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (hoc anh)) ky nang ma hoa. ((hieu ve) OR (hieu va)) cham thuc va hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (hoc anh)) ky nang ma hoa. ((hieu ve) OR (hieu va)) cham thuc va hanh vi cua triet*.