While Chrome allows you to search for links in your history via keywords and page titles, it doesn't go deeper than that. If you're after a way to search the actual content of those pages to make it easier to find them in your history, then you should check out WorldBrain.
The extension is available free via the Chrome Web Store and provides more expansive options for sifting through your browser history.
Not only does it provide full-text searching of pages, but also PDFs. It'll go through both your visited pages and bookmarks, which can be helpful if you favourite a lot of sites. It even support regular expressions, if you want to funky with your queries.
Once installed, all you have to do is use W + Space or the tab key to get started. It's pretty straightforward to use, however, if you're wondering how it works in more detail, you can check out the extension's source code repository on GitHub.