Perhaps you should try some spelling variations:
trinh khau » trinh khai, trinh kham, trinh khac
trinh nhan » trinh han, trinh phan, trinh nha
khau luan » khoa luan, phap luan, pham luan
cuoi viet » nguoi viet, co viet, nuoc viet
hai viet » thai viet, mai viet, tai viet
cao luan » cao lan, cao quan, dao luan
dang van » hoang van
dot viet » dat viet, do viet, doc viet
cao xuan » dao xuan, cao quan, ngo xuan
co cuoi » co nuoi, cho cuoc, co nguoi
cac cay » cac cam, cac cap, tac cay
cac cau » bac cau, cac cam, cac cap
cac mau » cam mau, sach mau
luan va » luan van, luat va
co hai » co dai, co hoi, o hai
ca cay » cua cay, ca cac, ca cao
cay co » cac co, tay co, cay cong
ca cau » can cau, cua cau, ca cac
va ca » va cac, va cao, va cai

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) or (cao xuan)) va ((((cac cau) or (ca cau))) or (cac mau)) co hai viet nam ) or ((( cong trinh khau luan va ca cay co dot viet nam ) or ( cong trinh nhan ((dang van) OR (hang va)) cac cay co cuoi viet nam ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( cong trinh ((cao luan) OR (cao xuan)) va ((((cac cau) OR (ca cau))) OR (cac mau)) co hai viet nam ) OR ((( cong trinh khau luan va ca cay co dot viet nam ) OR ( cong trinh nhan ((dang van) OR (hang va)) cac cay co cuoi viet nam )))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( cong trinh ((cao luan) or (cao xuan)) va ((((cac cau) or (ca cau))) or (cac mau)) co hai viet nam ) or ((( cong trinh khau luan va ca cay co dot viet nam ) or ( cong trinh nhan ((dang van) OR (hang va)) cac cay co cuoi viet nam ))))".
• Adding a wildcard symbol may retrieve word variants: (( cong trinh ((cao luan) or (cao xuan)) va ((((cac cau) or (ca cau))) or (cac mau)) co hai viet nam ) or ((( cong trinh khau luan va ca cay co dot viet nam ) or ( cong trinh nhan ((dang van) OR (hang va)) cac cay co cuoi viet nam ))))*.