Best approach to surface documents stored in salesforce in appian ?

Hi,

     We want to surface/view (not store ) salesforce documents in Appian . We already have an Salesforce connected system , we uses  SOQL integrations to expose the data points . I was just wondering can we use SOSL with the same connected system to return the documents (using RETURNING Document clause in SOSL).  Not sure whether SOSL can return docs . Or we need integrations with salesforce REST api to get the documents in Appian . Our users just have to view the documents on demand. We don't want to save them as Appian docs. Can anyone worked on similar use cases . Your inputs will be appreciated.

Thanks in advance,

Mike