Perhaps you should try some spelling variations:
occasional letters » occasional notes, occasional prayers, occasional papers
occasional writer » occasional notes, occasions written
occasional letter » occasional verse, occasional notes
22 number » 2 number, 12 numbers, 2.4 number
21 number » 2 number, 1 number, 11 number

Try widening your search to All Fields.

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: %((((((22occasional letter) OR (occasional letters))) OR (occasional writer))) OR (occasional letter)) %((22 number) OR (21 number)) 1%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%((((((22occasional letter) OR (occasional letters))) or (occasional writer))) or (occasional letter)) %((22 number) or (21 number)) 1%22".
• Adding a wildcard symbol may retrieve word variants: %((((((22occasional letter) OR (occasional letters))) or (occasional writer))) or (occasional letter)) %((22 number) or (21 number)) 1%22*.