Perhaps you should try some spelling variations:
cuon sach » duong sach, cuoc cach, nuoc sach
hanh tai » thanh tai, hang tai, han tai
co sach » bo sach, hoc sach
va hanh » van hanh, va thanh, va danh
cac tac » cac toc, cac bac, cac dac
cac tuc » cac toc, cac tu, cac nuoc
hieu va » lieu va, hieu qua
hang xa » hoang xa, hang va, hang ca
ly hang » ly quang
cuc tre » duc tre, cua tre, cuu tre

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((co sach) or (cuon sach)) ly hang xa hoi. hieu va ((cac tuc) or (cac tac)) va hanh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((co sach) OR (cuon sach)) ly hang xa hoi. hieu va ((cac tuc) OR (cac tac)) va hanh tai cuc tre.
• Adding a wildcard symbol may retrieve word variants: ((co sach) or (cuon sach)) ly hang xa hoi. hieu va ((cac tuc) or (cac tac)) va hanh tai cuc tre*.