Perhaps you should try some spelling variations:
"a regional conferences" » "a regional conference", "a regional consequences", "a regional differences"
"its regional convergence" » "its global convergence", "its region convergence"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("a regional conferences") OR ("its regional convergence"))*.
• Removing quotes may allow a broader search: (( a regional conferences ) or ( its regional convergence ))*.