I want to setup my search in a way that when I search for information or documents in my search site, it allows me to search using information inside the document.
What do I need to configure?
You'll need to use and IFilter to crawl the content of PDF-documents. It should work out of the box for Office-documents.
Here's a detailed tutorial (I haven't tried it)
You have to install an IFilter in Sharepoint. For example the Adobe PDF iFilter 9.0. More information on http://support.microsoft.com/kb/2293357