Perhaps you should try some spelling variations:
"motor neurone disease" » "motor neuroe disease"
"motor neuron disease" » "motor neuro disease"
"motor neuronal disease" » "motor neuroal disease", "motor neural disease"
"motor neurons disease" » "motor neuros disease"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("motor neurone disease") or ((((("motor neuron disease") OR ("motor neuronal disease"))) or ("motor neutron disease"))))) or ("motor neurons disease"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("motor neurone disease") OR ((((("motor neuron disease") OR ("motor neuronal disease"))) OR ("motor neutron disease"))))) OR ("motor neurons disease")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"motor neurone disease\") or (((((\"motor neuron disease\") OR (\"motor neuronal disease\"))) or (\"motor neutron disease\"))))) or (\"motor neurons disease\"))".
• Removing quotes may allow a broader search: (((( motor neurone disease ) or ((((( motor neuron disease ) OR ( motor neuronal disease ))) or ( motor neutron disease ))))) or ( motor neurons disease )).
• Adding a wildcard symbol may retrieve word variants: (((("motor neurone disease") or ((((("motor neuron disease") OR ("motor neuronal disease"))) or ("motor neutron disease"))))) or ("motor neurons disease"))*.