Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
thanh dai » thanh tai, thanh dat, thanh oai
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
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet
cuu ve » cuu va

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