Perhaps you should try some spelling variations:
ban danh » ban doanh, ban hanh, ban dan
lang van » dang van, tang van, hoang van
sach thu » sach thue, sach thieu, sach tham
tu sach » thu sach, su sach, te sach
hoi cua » hoi chuc
ban anh » ban hanh, ban banh, bang anh
qua cac » cua cac
cac xuc » cam xuc, cac nuoc, chat xuc
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach thu ((nang xa) or (lang van)) hoi. hieu qua cac xuc ((ban anh) OR (ban danh)) hoi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thu ((nang xa) OR (lang van)) hoi. hieu qua cac xuc ((ban anh) OR (ban danh)) hoi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach thu ((nang xa) or (lang van)) hoi. hieu qua cac xuc ((ban anh) OR (ban danh)) hoi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach thu ((nang xa) or (lang van)) hoi. hieu qua cac xuc ((ban anh) OR (ban danh)) hoi cua tre*.