Perhaps you should try some spelling variations:
trinh cao » trinh chao, trinh co, trinh cau
cao lanh » cao lan, cao anh, cao danh
dot viet » dat viet, do viet, doc viet
cao cac » cho cac, cao cap, ca cac
luan va » luan van, luat va
lang va » lang van, hang va, lang ha
lanh va » hanh va, anh va, lanh dao
cac co » cac cong
co loi » co hoi
va cao » va cac, va co, va dao
co toi » cho toi, co hoi, co doi

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( cong trinh cao ((lang va) or (luan va)) cao cac ((co toi) or (co loi)) viet nam ) or ( chuong trinh cao lanh va cao cac co dot viet nam ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( cong trinh cao ((lang va) OR (luan va)) cao cac ((co toi) OR (co loi)) viet nam ) OR ( chuong trinh cao lanh va cao cac co dot viet nam )).
• Adding a wildcard symbol may retrieve word variants: (( cong trinh cao ((lang va) or (luan va)) cao cac ((co toi) or (co loi)) viet nam ) or ( chuong trinh cao lanh va cao cac co dot viet nam ))*.