Perhaps you should try some spelling variations:
thanh dat » thanh san, thanh hai, thanh van
thanh dai » thanh hai, thanh tai, thanh oai
hieu van » hieu va, thien van, lieu va
chang xu » chang xue, chao xu, thong xu
ban duc » ban duoc, van duc, ban dac
te sach » toc sach
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
hang x » nang x, hoang xa, hang nxb

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty ((hang x) or (chang xu)) hoi. hieu van ban duc va ((thanh dai) OR (thanh dat)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((hang x) OR (chang xu)) hoi. hieu van ban duc va ((thanh dai) OR (thanh dat)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty ((hang x) or (chang xu)) hoi. hieu van ban duc va ((thanh dai) OR (thanh dat)) cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ty ((hang x) or (chang xu)) hoi. hieu van ban duc va ((thanh dai) OR (thanh dat)) cua tre*.