Perhaps you should try some spelling variations:
doanh van » doan van, doanh va, doanh ban
thu sach » tu sach, thuat sach, thuoc sach
dang van » hoang van, hang va
hieu ve » hieu va, hieu van
tu tong » tu tuong, tu trong, tu dong
tu tang » tuc tang, tu trang, tu lang
cuu tre » cua tre, cau tren, cau treo
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cam xuc va ((dang van) or (doanh van)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cam xuc va ((dang van) OR (doanh van)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cam xuc va ((dang van) or (doanh van)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cam xuc va ((dang van) or (doanh van)) cuu tre*.