Perhaps you should try some spelling variations:
"michael della author" » "michael kelly author", "michael heller author", "michael de author", "michael cells author", "michael wells author"
"michael only author" » "michael one author", "michael orey author", "michael odell author", "michael any author", "michael cowley author"

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: (("michael della author") OR ("michael only author")).
• Removing quotes may allow a broader search: (( michael della author ) or ( michael only author )).
• Adding a wildcard symbol may retrieve word variants: (("michael della author") or ("michael only author"))*.