Call numbers are numbers and letters that librarians put on labels to organize all kinds of library materials -books, videos, posters, models, etc. By keeping books and other items in call number order, we can easily find those items. A misshelved book is a lost book.
Pre-filter your search
Use the filtering and refinement tools to limit or focus your search before you begin.
For instance, if you want to make sure the book (or article- this applies to them, too) is about your subject, use a title field search. Usually, the search tool you are using will have a dropdown menu from which you can select "title" to search for your keyword or keywords in the title fields of the records.
Think like a thesaurus when you are getting started on something you know little to nothing about. It might take you some time to figure out the terminology being used by the experts in the field.
Try these keywords for the topic of evolution: evolution, natural selection, speciation, species, adaptation, mutation, uniformitarianism, genetic drift, selection pressure, allele frequency.
Most public and academic libraries provide a service called Interlibrary loan - lending between libraries. If your local public, school, or academic library does not have the book or video you need, you can most likely borrow from another library by using this service.
There are also electronic books (e-books) that can be borrowed (access to them will time out at the due date) from public libraries with which you have a membership. You can read them on your smart phone, tablet, or computer. Adobe Overdrive is the software needed to borrow books like this.