Perhaps you should try some spelling variations:
chuong trinh » cong trinh
trinh cac » trinh cau, trinh chat, trinh chao
soi viet » so viet, doi viet, noi viet
cac lanh » cay lanh, cac banh, cac lang
hoi viet » hai viet, thai viet, cuoi viet
cac cap » cao cap, cac cam, cac cau
dao cac » do cac, sao cac, tao cac
oi viet » o viet, cuoi viet, gioi viet
hanh va » hanh vi
cac tai » cao tai, cac bai, cac dai
tai co » mai co, tai so, tri co
cap do » cau do
do oi » do moi, do voi, do o

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( chuong trinh cac ((hanh va) OR (hang va)) cac tai co ((soi viet) or (hoi viet)) nam ) or ((( chuong trinh cac lanh dao cac cap do ((soi viet) or (hoi viet)) nam ) or ( chuong trinh cac lanh dao cac cap do oi viet nam ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( chuong trinh cac ((hanh va) OR (hang va)) cac tai co ((soi viet) OR (hoi viet)) nam ) OR ((( chuong trinh cac lanh dao cac cap do ((soi viet) OR (hoi viet)) nam ) OR ( chuong trinh cac lanh dao cac cap do oi viet nam )))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( chuong trinh cac ((hanh va) OR (hang va)) cac tai co ((soi viet) or (hoi viet)) nam ) or ((( chuong trinh cac lanh dao cac cap do ((soi viet) or (hoi viet)) nam ) or ( chuong trinh cac lanh dao cac cap do oi viet nam ))))".
• Adding a wildcard symbol may retrieve word variants: (( chuong trinh cac ((hanh va) OR (hang va)) cac tai co ((soi viet) or (hoi viet)) nam ) or ((( chuong trinh cac lanh dao cac cap do ((soi viet) or (hoi viet)) nam ) or ( chuong trinh cac lanh dao cac cap do oi viet nam ))))*.