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