Perhaps you should try some spelling variations:
cau thuc » cau truc, cuu thuc, can thuc
vat hanh » vat thanh, van hanh, va hanh
hanh tai » thanh tai, hang tai, han tai
sach ty » sach tu, sach thu, xach tay
hieu ve » hieu va, hieu van
tai cuu » tai cuc, tai buu, tai cua
cuu tre » cua tre, cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sach y)) nang x hoi. ((hieu ve) or (hieu qua)) cau thuc vat hanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) nang x hoi. ((hieu ve) OR (hieu qua)) cau thuc vat hanh tai cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach y)) nang x hoi. ((hieu ve) or (hieu qua)) cau thuc vat hanh tai cuu tre*.