Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cua triet » cua viet, va triet
hanh doi » thanh doi, hanh noi, hang doi
thu sach » tu sach, thuat sach, thuoc sach
su triet » su viet, su tien, ve triet
tang ma » mang may, tang van
hieu va » lieu va, hieu qua
va tham » van tham, va cham, va thanh
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
nang ma » sang ma, nang cao, mang may

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky ((nang ma) or (tang ma)) hoa. hieu va tham thuc va hanh doi ((cua triet) OR (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang ma) OR (tang ma)) hoa. hieu va tham thuc va hanh doi ((cua triet) OR (su triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((nang ma) or (tang ma)) hoa. hieu va tham thuc va hanh doi ((cua triet) OR (su triet))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang ma) or (tang ma)) hoa. hieu va tham thuc va hanh doi ((cua triet) OR (su triet))*.