Perhaps you should try some spelling variations:
"direct neural interface" » "directo neural interface", "director neural interface", "directed neural interface", "direct neuronal interface"
"directa neural interface" » "directoa neural interface", "directora neural interface", "directeda neural interface", "directa neuronal interface"
"direct neural interfaces" » "directo neural interfaces", "director neural interfaces", "directed neural interfaces", "direct neuronal interfaces"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("direct neural interface") OR ("directa neural interface"))) OR ("direct neural interfaces"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"direct neural interface\") OR (\"directa neural interface\"))) OR (\"direct neural interfaces\"))*".
• Removing quotes may allow a broader search: (((( direct neural interface ) OR ( directa neural interface ))) OR ( direct neural interfaces ))*.