Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
nam thuc » nam thuoc, am thuc, nam thu
hieu van » hieu va, thien van, lieu va
nham thu » nham thuc, nam thu, pham thu
cuu tre » cua tre, cau tren, cau treo
nang ma » tang ma, sang ma, nang cao
va hanh » van hanh, va thanh, va danh
vi cuu » vi luu, vinh cuu
tu cai » tu cac, tu can, tu bai
cai ky » cao ky, cac ky, cam ky
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cai ky nang ma hoi. hieu van ((tham thuc) or (((nham thu) or (nam thuc)))) va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cai ky nang ma hoi. hieu van ((tham thuc) OR (((nham thu) OR (nam thuc)))) va hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu cai ky nang ma hoi. hieu van ((tham thuc) or (((nham thu) or (nam thuc)))) va hanh vi cuu tre*.