Perhaps you should try some spelling variations:
trinh cong » trinh dung
trinh chao » trinh chat, trinh han, trinh giao
chao luan » khao luan, phap luan, khau luan
cong lan » cong luan, cong lang, cong san
hoi viet » hai viet, thai viet, cuoi viet
loi viet » loai viet, doi viet, noi viet
trinh co » trinh do, trinh hoa, trinh ky
hoc viet » hoc hien
cac bac » cac bai, cac ban, cac cach
oi viet » o viet, cuoi viet, gioi viet
cac cay » ca cay, cac cam, cac cap
luan va » luan van, luat va
co lan » cao lan, co ban, co dan
bac co » bac cao, bac bo, cac co
cay co » cac co, tay co, cay cong
lan va » lanh va, lan van, lang va
co loi » co hoi

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 cong lan va cac cay co hoc viet nam ) or ( cong trinh co lan va cac bac co ((hoi viet) OR (oi viet)) nam ))) or ( cong trinh chao luan va cac cay co loi viet nam ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( cong trinh cong lan va cac cay co hoc viet nam ) OR ( cong trinh co lan va cac bac co ((hoi viet) OR (oi viet)) nam ))) OR ( cong trinh chao luan va cac cay co loi viet nam )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( cong trinh cong lan va cac cay co hoc viet nam ) or ( cong trinh co lan va cac bac co ((hoi viet) OR (oi viet)) nam ))) or ( cong trinh chao luan va cac cay co loi viet nam ))".
• Adding a wildcard symbol may retrieve word variants: (((( cong trinh cong lan va cac cay co hoc viet nam ) or ( cong trinh co lan va cac bac co ((hoi viet) OR (oi viet)) nam ))) or ( cong trinh chao luan va cac cay co loi viet nam ))*.