Sharepoint folder data source troubles

van_r yes you can use a parameter as well to pass the folder path like below. below I have used a parameter Folder_path to pass the value to filter sharepoint folder. Please note that by default initially when you connect to sharepoint folder it will show the list of all files in that sharepoint folder. You will have to define a criteria to filters files. In this example I have used StartWith filter option to filter files based on the name of sub-folder

let
Source = SharePoint.Files("https://xxxxxxxxxxxxxxxxxxxxx", [ApiVersion = 15]),
#"Filtered rows" = Table.SelectRows(Source, each Text.StartsWith([Folder Path], "https://xxxxxxxxxxxxxxxxxxxxxxxx/")),
#"Filtered Rows" = Table.SelectRows(#"Filtered rows", each Text.StartsWith([Folder Path], Folder_Path))
in
#"Filtered Rows"