Perhaps you should try some spelling variations:
cau thuc » cuu thuc, can thuc, cau phuc
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
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 nang x hoi. ((hieu ve) or (hieu qua)) ((cau thuc) or (cau truc)) va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang x hoi. ((hieu ve) OR (hieu qua)) ((cau thuc) OR (cau truc)) va hanh tai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang x hoi. ((hieu ve) or (hieu qua)) ((cau thuc) or (cau truc)) va hanh tai cua tre*.