Perhaps you should try some spelling variations:
electronic resources » electronic resource
electronic sources » electron sources, electronic resource, electron source
3.2 apache » 2.2 apache, 3.6 apache, 3.2.4 apache
3 apache » 1 apache
4 apache » 1 apache, 5 apache, 6 apache

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: %22spark %((((electronic sources) OR (electronic resources))) OR (electronic devices)) %((3.2 apache) OR (((3 apache) OR (((4 apache) OR (_ apache)))))) software foundation%29%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22spark %((((electronic sources) OR (electronic resources))) or (electronic devices)) %((3.2 apache) or (((3 apache) or (((4 apache) or (_ apache)))))) software foundation%29%22".
• Adding a wildcard symbol may retrieve word variants: %22spark %((((electronic sources) OR (electronic resources))) or (electronic devices)) %((3.2 apache) or (((3 apache) or (((4 apache) or (_ apache)))))) software foundation%29%22*.