Running Outlook 2013 with a cached exchange mode setting of 6 months. 

Issue is if I search for data outside of the 6 months I receive zero results.  I do get the link stating more data is available on exchange and if I click that link search will not search any of the new data that was just downloaded to the mailbox. 

It seems that search within outlook is limited to the OST.  is this true?  I have been unable to find any MS documentation that states this.

When you search for an item beyond 6 months, it gives you an option there saying more data is available on the server. Now, my reply below is considering you have a mailbox on Exchange server... if not, please ignore this comment as this might not be relevant.

If clicking on that and search does not return anything there could be 2 reasons for that

1. The item searching does not exist in your mailbox (I am pretty sure that it is not the case)

2. Your Exchange server database containing your mailbox does not have the items indexed - either indexing is happening (crawling) or indexing for your database has failed.