AND, OR, NOT

You can use Boolean operators – AND, OR, NOT – to define the relationship between the words or phrases in your search.

Note: In a Basic search, you can type Boolean operators in the Find field; in a Power search, you can select them.

• Searching for cats AND dogs results in a list of titles that mention both cats and dogs.

• Searching for cats OR dogs results in a list of titles that mention cats, or dogs, or both.
• Searching for cats NOT dogs results in a list of titles about cats that do not mention dogs.
• Using a second Boolean operator to add a third search term can either contract or expand the search results. The search order follows the same logic as the equation ( a + b ) + c :
  • Searching for cats AND dogs AND fish results in a list of titles that mention cats, dogs and fish.
  • Searching for cats AND dogs OR fish results in a list of titles that include both cats and dogs, plus all the titles that mention fish.
  • Searching for cats AND dogs NOT fish results in a list of titles that include cats and dogs but do not mention fish.

Keep in mind that OR expands your search.

Do not use OR when you mean NOT.

Example: You want to find a nonfiction book by Isaac Asimov that is not about science. If you search for asimov NOT fiction OR science, your results will not include fiction, but will contain science. Instead, search for asimov NOT fiction NOT science.

If the second Boolean operator is OR, the search could have some unexpected results.

Example: You are looking for books about cats that also mention either dogs or fish. If you search for cats AND dogs OR fish, the search results will be dominated by titles about fish. Instead, you should search for dogs OR fish AND cats.