Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
tham thuc » nham thuc, pham thuc, tam thuc
thanh vai » thanh hai, thanh van, thanh tai
thuc dan » thuc hanh, hoc dan, thuc vat
va triet » va trien, ve triet, cua triet
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
va tham » van tham, va cham, va thanh
sac ky » cac ky, sai ky
thiet » thieu

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) or (sac ky)) nang ma hoa. lieu va tham thuc dan thanh vai ((va triet) OR (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang ma hoa. lieu va tham thuc dan thanh vai ((va triet) OR (va thiet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) nang ma hoa. lieu va tham thuc dan thanh vai ((va triet) OR (va thiet))".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) nang ma hoa. lieu va tham thuc dan thanh vai ((va triet) OR (va thiet))*.