code: public FolderItemResponse search(String accountId, String searchFolderId) throws ApiException {
      return search(accountId, searchFolderId, null);
    }
docs: Gets a list of envelopes in folders matching the specified criteria.
  Retrieves a list of envelopes that match the criteria specified in the query.  If the user ID of the user making the call is the same as the user ID for any returned recipient, then the userId property is added to the returned information for those recipients.
  @param accountId The external account number (int) or account ID Guid. (required)
  @param searchFolderId Specifies the envelope group that is searched by the request. These are logical groupings, not actual folder names. Valid values are: drafts, awaiting_my_signature, completed, out_for_signature. (required)
  @return FolderItemResponse