Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
han danh » van danh, phan dang, nhan dang
ban danh » ban doanh, ban hanh, ban dan
sang tao » hang tai
te sach » toc sach
vi tham » vi pham, va tham, vi than
hieu vi » hieu voi, hieu va, hieu ve
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, nang ma, mang may
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky ((sang ma) OR (sang tao)) hoi. hieu vi tham thuc ((ban danh) or (han danh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((sang ma) OR (sang tao)) hoi. hieu vi tham thuc ((ban danh) OR (han danh)) dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((sang ma) OR (sang tao)) hoi. hieu vi tham thuc ((ban danh) or (han danh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((sang ma) OR (sang tao)) hoi. hieu vi tham thuc ((ban danh) or (han danh)) dai cua tre*.