Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vi » hanh vi, thanh va, thanh ve
sach ky » sach y, sach ty, sach kem
duc ban » duc tan, duc van, dua ban
lam duc » lam duoc, pham duc, nam duoc
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, mang may
luu tre » luu tru, cuu tre, luy tre
va lam » van lam, va lap
sac ky » cac ky, sai ky
vi luu » vi lua

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) or (nang cao)) hoi. hieu va lam duc ban thanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) ((nang ma) OR (nang cao)) hoi. hieu va lam duc ban thanh vi luu tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) ((nang ma) or (nang cao)) hoi. hieu va lam duc ban thanh vi luu tre*.