Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nam thuc » nam thuoc, am thuc, nam thu
hanh tai » thanh tai, hang tai, han tai
van hanh » van thanh, ban hanh, van anh
ly quang » le quang, vu quang
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
cam tuc » cam xuc, cam tu, dam thuc
van hoi » van hoa, van hoc, van hoe
ty lang » tay lang, ty xang, ty hang

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 ((ty lang) or (ly quang)) van hoi. lieu va ((cam tuc) OR (nam thuc)) van hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ty lang) OR (ly quang)) van hoi. lieu va ((cam tuc) OR (nam thuc)) van hanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((ty lang) or (ly quang)) van hoi. lieu va ((cam tuc) OR (nam thuc)) van hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((ty lang) or (ly quang)) van hoi. lieu va ((cam tuc) OR (nam thuc)) van hanh tai cua tre*.