Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh dai » hanh tai, hanh dao, vanh dai
sach ke » sach kem, sach de, sach che
ve chat » va chat, van chat
cua tre » cua te, cuu tre, cua triet
ve cham » va cham, vu cham, ve chim
may hoi » may thoi, tay hoi, mai hoi
ke mang » ke nang, ke trang
xuc va » duc va, tuc va, luc va

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 ke mang may hoi. hieu ((ve cham) OR (ve chat)) ((xuc va) or (thuc vat)) hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ke mang may hoi. hieu ((ve cham) OR (ve chat)) ((xuc va) OR (thuc vat)) hanh dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ke mang may hoi. hieu ((ve cham) OR (ve chat)) ((xuc va) or (thuc vat)) hanh dai cua tre*".