Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
nang tai » hang tai, tang tai, sang tai
hanh tai » thanh tai, hang tai, han tai
hanh dai » hanh dao, vanh dai, thanh dat
hieu voi » hieu moi, lieu voi, hieu loi
thuc va » thuc vat, thuc dan, thuc day
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu vi » hieu va, hieu ve, hien vi
tai hoi » tai khoi, dai hoi, tai hai
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: su sach ky nang tai hoi. ((hieu vi) or (hieu voi)) tham thuc va ((hanh dai) OR (hanh tai)) cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang tai hoi. ((hieu vi) OR (hieu voi)) tham thuc va ((hanh dai) OR (hanh tai)) cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang tai hoi. ((hieu vi) or (hieu voi)) tham thuc va ((hanh dai) OR (hanh tai)) cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang tai hoi. ((hieu vi) or (hieu voi)) tham thuc va ((hanh dai) OR (hanh tai)) cua te*.