Perhaps you should try some spelling variations:
"astronomy and astrophysics summary" » "astronomy and astrophysics gamma", "astronomy and physics summary", "astronomy and astrophysics history"
"astronomy and astrophysics stars" » "astronomy and astrophysics saas", "astronomy and astrophysics state", "astronomy and astrophysics history"
"astronomy and astrophysics sun" » "astronomy and astrophysics _"

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: (((("astronomy and astrophysics summary") OR ("astronomy and astrophysics sun"))) OR ("astronomy and astrophysics stars")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"astronomy and astrophysics summary\") OR (\"astronomy and astrophysics sun\"))) or (\"astronomy and astrophysics stars\"))".
• Removing quotes may allow a broader search: (((( astronomy and astrophysics summary ) OR ( astronomy and astrophysics sun ))) or ( astronomy and astrophysics stars )).
• Adding a wildcard symbol may retrieve word variants: (((("astronomy and astrophysics summary") OR ("astronomy and astrophysics sun"))) or ("astronomy and astrophysics stars"))*.