Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
de thanh » le thanh
cham cuu » cap cuu, chat cua
so sach » so sanh, bo sach, co sach
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
mang xa » lang xa, mang may, dang xay
nang xa » nang x, lang xa, ang xa
cuu de » cuu ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu ve cham cuu de thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((((nang xa) OR (mang xa))) OR (nang ma)) hoi. hieu ve cham cuu de thanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu ve cham cuu de thanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach y ((((nang xa) OR (mang xa))) or (nang ma)) hoi. hieu ve cham cuu de thanh dai cua tre*.