Perhaps you should try some spelling variations:
"occasional prayers; occasional letter" » "occasional poems; occasional letter", "occasional writer; occasional letter", "occasional prayers; occasional writer", "occasional prayers; occasional notes"
"occasional prayers; occasional verse" » "occasional poems; occasional verse", "occasional writer; occasional verse"
"occasions written; occasional letter" » "occasions written; occasional writer", "occasions written; occasional notes", "occasion written; occasional letter", "occasioned written; occasional letter"

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: (("occasions written; occasional letter") OR ((("occasional prayers; occasional letter") OR ("occasional prayers; occasional verse")))).
• Removing quotes may allow a broader search: (( occasions written; occasional letter ) or ((( occasional prayers; occasional letter ) or ( occasional prayers; occasional verse )))).
• Adding a wildcard symbol may retrieve word variants: (("occasions written; occasional letter") or ((("occasional prayers; occasional letter") or ("occasional prayers; occasional verse"))))*.