Given our resources and current technologies, it is safe to say, that in our lifetimes you will probably not be able to access all of our vast holdings by searching by subject and having all relevant documents appear. The best we can hope for is getting our finding aids and other search-tools online. Once you begin your archival research you will have to do your own digging in the records, looking for nuggets of evidence to piece your stories together. Our website and staff can help pinpoint where you need to look, but it will be for you, in most instances, to do your own research, your own digging into the records. And in doing your research, it is quite important to remember the differences between libraries and archives.
Libraries arrange their books generally by subject.
Thus if you want something on gardening, the books will probably be physically together on the shelves. Like wise, library card indexes can also be searched by subject. This is not always the case with archives. Archives are arranged by provenance, i.e., which entity created or received them, and then each series of records of an agency are arranged in some particular order. Sometimes this order is alphabetically by subject, sometimes it is by some type of alphabetical or numerical or an alpha-numeric filing scheme, and at other times it is numerically by some form of case file number, which you would need an index to look up specific case files.