Perhaps you should try some spelling variations:
occasional letter » occasional writer, occasional verse, occasional notes
2.4 number » 22 number
2f number » 22 number, 23 number, 29 number
21 number » 1 number, 22 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: %occasional letter %((((((((2f number) OR (21 number))) OR (2.4 number))) OR (2 number))) OR (3 number)) 1%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%occasional letter %((((((((2f number) OR (21 number))) or (2.4 number))) or (2 number))) or (3 number)) 1%22".
• Adding a wildcard symbol may retrieve word variants: %occasional letter %((((((((2f number) OR (21 number))) or (2.4 number))) or (2 number))) or (3 number)) 1%22*.