Perhaps you should try some spelling variations:
nghien nam » nghiep nam, nguyen nam, nghe nam
hoc phien » thuoc phien, hoc nghien, hoc phan
phien nam » hien nay, phien ban, vien nam
danh cac » danh ca, hanh cac, dan cac
cac vung » cac ung, cac chung, cach dung
hoc vien » hoc viet, hoc tieng, hoc vi
dinh cac » tinh cach, dinh chuc, dinh chau
canh tac » canh tay, canh giac, cong tac
vung hoc » dung hoc, vung moc, trung hoc
dung mo » dung co, dung hoc
cac van » cac dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((( danh cac vung hoc phien nam ) or ( canh tac ((dung mo) or (dung cho)) nghien nam ))) or ((( danh cac van ((hoc vien) or (hoc hien)) nam ) or ( dinh cac van ((hoc vien) or (hoc hien)) nam ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((( danh cac vung hoc phien nam ) OR ( canh tac ((dung mo) OR (dung cho)) nghien nam ))) OR ((( danh cac van ((hoc vien) OR (hoc hien)) nam ) OR ( dinh cac van ((hoc vien) OR (hoc hien)) nam )))).
• Adding a wildcard symbol may retrieve word variants: (((( danh cac vung hoc phien nam ) or ( canh tac ((dung mo) or (dung cho)) nghien nam ))) or ((( danh cac van ((hoc vien) or (hoc hien)) nam ) or ( dinh cac van ((hoc vien) or (hoc hien)) nam ))))*.