Perhaps you should try some spelling variations:
thanh tai » thanh toan, doanh tai, thanh san
thanh hai » thanh phan, thanh hoa, thanh san
sach thu » sach thue, sach thieu, sach tham
nang mai » nang ma, nang tai, lang mai
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, xach tay
mai hoi » mai khoi, dai hoi, lai hoi
cua tre » cua te, cuu tre, cua triet
cuu va » cuu van, cuu ve
ve cap » ve cac, le cap, ve cai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) or (sach thu)) nang mai hoi. hieu ve cap cuu va ((thanh hai) or (thanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) nang mai hoi. hieu ve cap cuu va ((thanh hai) OR (thanh tai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach thu)) nang mai hoi. hieu ve cap cuu va ((thanh hai) or (thanh tai)) cua tre*.