Perhaps you should try some spelling variations:
doanh van » doanh va, doanh ban, doanh nhan
cac truc » cau truc, cac tru, cac trung
toc sach » hoc sach, doc sach, thuoc sach
doan van » doan va, hoang van, luan van
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
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: ((te sach) OR (toc sach)) ky dang xa hoi. hieu ve cac truc va ((doanh van) or (doan van)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky dang xa hoi. hieu ve cac truc va ((doanh van) OR (doan van)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky dang xa hoi. hieu ve cac truc va ((doanh van) or (doan van)) cua tre*".