I have a search query web part that I am running that looks like the following.
(path:"PATH TO FOLDER" AND ContentTypeId:0x0120D520*)
This path contains links to document sets. I am trying to recreate this query in a REST call.
I've tried variations of things like the url below with no luck.
/_api/web/GetFolderByServerRelativeUrl('Path to folder')/Files?$filter=startswith(ContentTypeId,'0x0120D520')