I'm just getting into KQL and using the query builder with custom search result sources in my site collection. I've found this documentation on msdn and that is very helpful, but I don't think it is complete.
I'm seeing things in the default queries and on tutorial sites like:
contentclass:sts_listitme OR IsDocument:True
I'm guessing those are property queries, but I'm not finding much documentation on them especially with regards to SP 2013. I know that the properties available will change with different installations and custimizations. But I'm wondering if there is a list of them based on the default SP features? Things like IsDocument and contentclass aren't anything I set up. And where would I find the difference between IsDocument:True and spcontenttype:document?
Does anybody have a good reference for these? Or a way to discover the possible properties and values?