Perhaps you should try some spelling variations:
"extended cross-correlations" » "extended cost-correlations", "extended class-correlations", "detrended cross-correlations"
"defense cross-correlations" » "defense cost-correlations", "dense cross-correlations", "defense actors-correlations"

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: (("extended cross-correlations") OR ("defense cross-correlations")).
• Removing quotes may allow a broader search: (( extended cross-correlations ) or ( defense cross-correlations )).
• Adding a wildcard symbol may retrieve word variants: (("extended cross-correlations") or ("defense cross-correlations"))*.