Perhaps you should try some spelling variations:
"normal model artificial neural network" » "normal femoral artificial neural network", "normal real artificial neural network", "normal model artificial neural networks", "neural model artificial neural network", "novel model artificial neural network"
"neutron star artificial neural network" » "neutron can artificial neural network", "neutron real artificial neural network", "neutron toward artificial neural network", "neutron star artificial neural networks"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("neutron star artificial neural network") or ("normal model artificial neural network"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("neutron star artificial neural network") OR ("normal model artificial neural network")).
• Removing quotes may allow a broader search: (( neutron star artificial neural network ) or ( normal model artificial neural network )).
• Adding a wildcard symbol may retrieve word variants: (("neutron star artificial neural network") or ("normal model artificial neural network"))*.