Perhaps you should try some spelling variations:
chuong tinh » chuong trinh, khuong tinh, thuong tinh
chat van » chat va, chat ban, chat ran
trinh do » trinh ky
trinh co » trinh cong, trinh hoa, trinh ky
so viet » hoc viet
oi viet » hoi viet, o viet, cuoi viet
cot loi » co loi, cot soi, mot loai
cot noi » cot soi, cong noi
tan van » tran van, tang van, luan van
lan van » luan van, lang van, san van
van va » van vat, van van, ban va
cay co » cac co, tay co, cay cong
cao co » cao cho, cac co, bao co
ca cay » cua cay, cac cay, ca cac
co oi » co hoi, co loi, co doi
co co » co so, vo co, co o
va ca » va cac, va cao, va cai

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: (((( chuong tinh chat van va ca ((cao co) OR (co co)) so viet nam ) OR ( chuong ((trinh co) OR (trinh do)) van va ca cay co oi viet nam ))) OR ( chuong tinh chat ((lan van) OR (tan van)) cua cac ((cot noi) OR (cot loi)) viet nam ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( chuong tinh chat van va ca ((cao co) OR (co co)) so viet nam ) or ( chuong ((trinh co) or (trinh do)) van va ca cay co oi viet nam ))) or ( chuong tinh chat ((lan van) or (tan van)) cua cac ((cot noi) or (cot loi)) viet nam ))~".
• Adding a wildcard symbol may retrieve word variants: (((( chuong tinh chat van va ca ((cao co) OR (co co)) so viet nam ) or ( chuong ((trinh co) or (trinh do)) van va ca cay co oi viet nam ))) or ( chuong tinh chat ((lan van) or (tan van)) cua cac ((cot noi) or (cot loi)) viet nam ))*.