Perhaps you should try some spelling variations:
doanh ban » doanh bat, doanh van, doanh nhan
cua triet » cua viet, su triet, va triet
va doanh » van doanh, vay doanh, va danh
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cao hoc » co hoc, cho hoc, chat hoc
hieu va » lieu va
thuc va » thuc vat, thuc dan, thuc day
ban cua » ban quan

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang cao hoc. ((hieu va) OR (hieu qua)) am thuc va doanh ban cua triet~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang cao hoc. ((hieu va) OR (hieu qua)) am thuc va doanh ban cua triet*.