Perhaps you should try some spelling variations:
doanh van » doan van, doanh va, doanh ban
thu sach » thuat sach, thuoc sach, thu hoach
danh vai » danh sai, danh va, dang van
cac duc » cac du, cao duc, cac dac
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
tang xa » trang xa, tang ma, lang xa
tu tang » tuc tang, tu trang, tu tong
tu sach » su sach, te sach, tu cach
ve cac » va cac, vien cac

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