Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van tham » van thanh, van tuan, van chat
sinh dai » sinh thai, si dai, sinh vat
nang ma » tang ma, sang ma, nang cao
va tham » va cham, va thanh, va thuat
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
tuc va » thuc va, tuc xa, duc va

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 y nang ma hoi. lieu ((va tham) or (van tham)) ((tuc va) or (truc va)) sinh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang ma hoi. lieu ((va tham) OR (van tham)) ((tuc va) OR (truc va)) sinh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang ma hoi. lieu ((va tham) or (van tham)) ((tuc va) or (truc va)) sinh dai cua tre*.