Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cham thuc » nham thuc, pham thuc, pham thuoc
va thanh » gia thanh, ban thanh, va tinh
thanh le » thinh le, thanh ve, thanh de
te sach » toc sach
sach ty » sach y, sach tu, sach thu
xang ha » lang ha, tang ha, dang ha
hieu ve » hieu va, hieu van
co viet » so viet, o viet, hoc viet

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 ty xang ha noi. hieu ve ((cham thuc) or (tham thuc)) va thanh le ((co viet) or (cua vat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty xang ha noi. hieu ve ((cham thuc) OR (tham thuc)) va thanh le ((co viet) OR (cua vat)).
• Adding a wildcard symbol may retrieve word variants: te sach ty xang ha noi. hieu ve ((cham thuc) or (tham thuc)) va thanh le ((co viet) or (cua vat))*.