To find books written about a specific person, do a Subject search in OSCAR (the library's catalog) and type the person's name (last name first).
If you are looking for books about a topic (not a person), do an Advanced search in OSCAR. If the first terms you type do not give you the results you want, try typing in various ways of describing your topic. Another good technique to find more on your topic is to use truncation. Instead of looking for "Silicon Valley and technology," put an asterisk at a strategic point in the word to find variations on it. For example, a search for tech* will find the words technology, technological, technologies, techie, techies, etc.
Once you find some books that look like what you want, click on the Subject links that appear in the full records for those books, and you will probably find even more books on the same topic. (For example, if you type "Silicon Valley and technology," you will find a few books, but clicking on the Subject heading "High technology industries - California - Santa Clara County - History" will reveal additional books to choose from.)
Your results will probably include printed books that can be found in the library building, as well as electronic books that can be read online. You can tell which books are e-books because no physical location is indicated, and the words "(Electronic Resource)" usually appear immediately following the title of the book. Click on the title of the book to open its record in OSCAR; then click the link in the middle of the screen to read the book online.