Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
vat thanh » dat thanh, gat thanh, tat thanh
thanh dat » thanh san, thanh hai, thanh van
tai khoi » tai khoa, mai khoi, tao khoi
so sach » so sanh, bo sach, co sach
tai hoi » dai hoi, tai hai, tai hoe
hieu vi » hieu voi, hieu va, hieu ve
vi tham » vi pham, va tham, vi than
dat cua » dai cua, day cua, mat cua
y nang » ky nang, ly nang, v nang
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y nang ((tai hoi) or (tai khoi)). hieu vi tham thuc vat thanh dat cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y nang ((tai hoi) OR (tai khoi)). hieu vi tham thuc vat thanh dat cua te.
• Adding a wildcard symbol may retrieve word variants: so sach y nang ((tai hoi) or (tai khoi)). hieu vi tham thuc vat thanh dat cua te*.