Perhaps you should try some spelling variations:
trinh khau » trinh khai, trinh kham, trinh khac
trinh nhan » trinh han, trinh phan, trinh nha
trinh bao » trinh dao, trinh ban, trinh bay
nhan dang » nhan dan, phan dang, tran dang
khau luat » khau luan, thau luat, phap luat
dang van » hoang van, hang va
bao quan » ban quan, van quan, tac quan
doi viet » dai viet, hoi viet, oi viet
hai viet » thai viet, mai viet, tai viet
quan va » quan vi, quan ha, luan va
cac mau » cam mau, sach mau
coc dat » hoc dat, chon dat, duoc dat
cac cay » ca cay, cac cam, cac cap
van cac » van hac, van cau, van bac
cac cau » bac cau, ca cau, cac cam
co doi » cho doi, co dot, co dai
cay co » cac co, tay co, cay cong
va cao » va cac, va co, va dao
co hai » co dai, co hoi, o hai
co dan » co ban, ca dan, cao dang
va ca » va cac, va cai, va cau

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