Perhaps you should try some spelling variations:
"motor neurone disease" » "motor neuronal disease", "motor neutrone disease", "motor neuroe disease", "motor neuronale disease"
"motor neutrone disease" » "motor neutron disease", "motor neutrino disease"
"motor neuron disease" » "motor neutron disease", "motor neuro disease", "motor neuronal disease"
"motor neurons disease" » "motor neutrons disease", "motor neuros disease", "motor neuronals disease", "motor neuronal disease"
"motor neuronals disease" » "motor neutronals disease", "motor neuroals disease", "motor neuronalals disease", "motor neuronal 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 neutrone disease"))) or ((("motor neuron disease") or ((("motor neurons disease") or ("motor neuronals disease"))))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("motor neurone disease") OR ("motor neutrone disease"))) OR ((("motor neuron disease") OR ((("motor neurons disease") OR ("motor neuronals disease")))))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"motor neurone disease\") OR (\"motor neutrone disease\"))) or (((\"motor neuron disease\") or (((\"motor neurons disease\") or (\"motor neuronals disease\"))))))".
• Removing quotes may allow a broader search: (((( motor neurone disease ) OR ( motor neutrone disease ))) or ((( motor neuron disease ) or ((( motor neurons disease ) or ( motor neuronals disease )))))).
• Adding a wildcard symbol may retrieve word variants: (((("motor neurone disease") OR ("motor neutrone disease"))) or ((("motor neuron disease") or ((("motor neurons disease") or ("motor neuronals disease"))))))*.