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