Perhaps you should try some spelling variations:
thuc day » thuc dan, thuc vat
day hanh » day nhanh, day thanh, dao hanh
hanh dai » hanh tai, hanh dao, vanh dai
sach ky » sach y, sach ty, sach kem
cao hoi » cau hoi, co hoi, cao hoc
ve pham » vi pham, v pham, ve phat
ve phan » va phan, ke phan, ve phat
sac ky » cac ky, sai ky
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: thu ((sach ky) or (sac ky)) nang cao hoi. hieu ((ve pham) OR (ve phan)) thuc day hanh dai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang cao hoi. hieu ((ve pham) OR (ve phan)) thuc day hanh dai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) nang cao hoi. hieu ((ve pham) OR (ve phan)) thuc day hanh dai cua te".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) nang cao hoi. hieu ((ve pham) OR (ve phan)) thuc day hanh dai cua te*.