Perhaps you should try some spelling variations:
occasional letters » occasional prayers, occasional papers
occasional writers » occasional drivers, occasional writings, occasional prayers
occasional letter » occasional verse
occasional writer » occasions written
occasional notess » occasional notices, occasional poems, occasion notes

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: (((( occasional letters; occasional letter ) OR ( occasional writers; occasional writer ))) OR ( occasional notess; occasional notes )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( occasional letters; occasional letter ) OR ( occasional writers; occasional writer ))) or ( occasional notess; occasional notes ))".
• Adding a wildcard symbol may retrieve word variants: (((( occasional letters; occasional letter ) OR ( occasional writers; occasional writer ))) or ( occasional notess; occasional notes ))*.