Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
ban hanh » ban hang
thuc ban » thuoc ban, thuc dan, thu ban
qua tham » qua cham, qua than, qua thanh
tay hoi » tay ho, tao hoi, tay thai
ke mang » ke nang, ke trang
ky mang » ky nang, ky dang, ky tang
vai cua » dai cua, hai cua, bai cua
lai cua » dai cua, hai cua, lai chau
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ((ky mang) or (ke mang)) tay hoi. hieu qua tham thuc ban hanh ((vai cua) OR (lai cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ((ky mang) OR (ke mang)) tay hoi. hieu qua tham thuc ban hanh ((vai cua) OR (lai cua)) viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ((ky mang) or (ke mang)) tay hoi. hieu qua tham thuc ban hanh ((vai cua) OR (lai cua)) viet*".