Perhaps you should try some spelling variations:
"michael perry author" » "michael berry author", "michael petry author", "michael barry author", "michael theory author", "michael hervey author", "michael murray author"
"michael henry author" » "michel henry author", "michael henein author", "michel henry's author", "michael theory author", "michael henry arthur", "michael hervey 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 perry author") OR ("michael henry author")).
• Removing quotes may allow a broader search: (( michael perry author ) or ( michael henry author )).
• Adding a wildcard symbol may retrieve word variants: (("michael perry author") or ("michael henry author"))*.