Perhaps you should try some spelling variations:
sach tin » sach tien, sach kinh, sach tren
doan van » doan va, hoang van, luan van
danh vai » danh sai, danh va, doanh van
tu sach » thu sach, su sach, te sach
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
mang xa » mang may, dang xay, mang cua
ve cam » ve cham, ve cac, va cam

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tin ((mang xa) OR (lang xa)) hoi. hieu ve cam duc va ((danh vai) OR (doan van)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tin ((mang xa) OR (lang xa)) hoi. hieu ve cam duc va ((danh vai) or (doan van)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach tin ((mang xa) OR (lang xa)) hoi. hieu ve cam duc va ((danh vai) or (doan van)) cua tre*.