If your required filter doesn't appear in the Other Filters list you will need to download it from EndNote Filters Webpage :
MAC users - Select your required filter, control-click and choose Save Linked File to "Downloads". The filter will now appear in your "Downloads" drag the filter file into your Filters folder. Located
HD\Applications\EndNote\Filters
Manually importing references using filters
If the database does not have a direct export option you will need to manually import the reference saved as a text file: