Perhaps you should try some spelling variations:
trinh khau » trinh khai, trinh kham, trinh khac
trinh phan » trinh han, trinh quan, thanh phan
trinh cao » trinh chao, trinh co, trinh cau
phan dang » phan dau, phan cong, nhan dan
khau luan » khoa luan, phap luan, pham luan
cao luan » cao lan, cao quan, cao xuan
dang van » hoang van, hang va
hai viet » thai viet, tai viet, dai viet
dot viet » dat viet, do viet, doc viet
mai viet » thi viet
van cac » van hac, van cau, van bac
luan va » luan van, luat va
cac cac » cac cach, ca cac, cac bac
oi viet » hoi viet, o viet, cuoi viet
va cua » va chua, via cua, ca cua
cay co » cay cong
tay co » ty co, tay o
cac co » cac cong

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 luan va cac cac co ((hai viet) or (mai viet)) nam ) or ((( cong trinh khau luan va cua ((cay co) or (tay co)) dot viet nam ) or ( cong trinh phan dang van cac ((cay co) or (tay co)) oi viet nam ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( cong trinh cao luan va cac cac co ((hai viet) OR (mai viet)) nam ) OR ((( cong trinh khau luan va cua ((cay co) OR (tay co)) dot viet nam ) OR ( cong trinh phan dang van cac ((cay co) OR (tay co)) oi viet nam )))).
• Adding a wildcard symbol may retrieve word variants: (( cong trinh cao luan va cac cac co ((hai viet) or (mai viet)) nam ) or ((( cong trinh khau luan va cua ((cay co) or (tay co)) dot viet nam ) or ( cong trinh phan dang van cac ((cay co) or (tay co)) oi viet nam ))))*.