Perhaps you should try some spelling variations:
lam thuoc » nam thuoc, am thuc, cay thuoc
lam duoc » nam duoc, luat duoc, tao duoc
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
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 ky) or (sac ky)) nang ma hoa. hieu van ((lam duoc) OR (lam thuoc)) va thanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang ma hoa. hieu van ((lam duoc) OR (lam thuoc)) va thanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang ma hoa. hieu van ((lam duoc) OR (lam thuoc)) va thanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang ma hoa. hieu van ((lam duoc) OR (lam thuoc)) va thanh vi cua tre*.