Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
thuc ban » thuoc ban, thuc dan, thu ban
nam thuc » nam thuoc, am thuc, nam thu
tai cuu » tai cuc, tai buu, tai cua
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
sach tu » sach thu, cach tu, sach uu
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach thu, xach tay
va nam » van nam, ha nam, va nay

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach tu) OR (sach ty)) ((nang ma) OR (nang x)) hoi. hieu va nam thuc ban thanh tai cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach tu) OR (sach ty)) ((nang ma) or (nang x)) hoi. hieu va nam thuc ban thanh tai cuu tre~".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach tu) OR (sach ty)) ((nang ma) or (nang x)) hoi. hieu va nam thuc ban thanh tai cuu tre*.