The user can upload files to all records that contain a specific keyword. Follow the below steps:
- Go to the "Mass File Upload" tab.
- Toggle the "Record Selection Mode" to ON.
- Select "Search" as the Search Mode.
- Choose the object from the "Select Object" dropdown against which you wish to upload the files.
- Enter the keyword in the search box and click on the "Select All" button just after the search box.
- All records containing the keyword will be selected.
- Click on the "Upload Files" button to upload files to these selected records.
PS: View Mass File Upload, Salesforce file upload app on Salesforce AppExchange: https://appexchange.salesforce.com/appxListingDetail?listingId=82cf236b-1ee8-4ea7-aebf-fd0c89fb93bd