Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach tu, sach thu
sach ky » sac ky, sach y, sach kem
thi van » thi lan, thi hanh, thi nang
vat dau » bat dau, va dau, van dau
dau dau » dan dau, dat dau, dau da
dau cua » dai cua, day cua, cau cua
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ky) or (sach ty)) nang xa hoi. ((thien van) OR (thi van)) cham thuc vat dau dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sach ty)) nang xa hoi. ((thien van) OR (thi van)) cham thuc vat dau dau cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) or (sach ty)) nang xa hoi. ((thien van) OR (thi van)) cham thuc vat dau dau cua tre".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) or (sach ty)) nang xa hoi. ((thien van) OR (thi van)) cham thuc vat dau dau cua tre*.