Doesn't that sound hip? Do you boolean? Heck yeah I boolean! I be booleaning all day long. I'm so tired of booleaning, man booleaning got me so busy today! What a boolean! Boolean that! Boolean don't even know what booleaning her. Boolean!
Basically, it's a way of advance searching with key phrases such as AND and OR.
If I want to search for baby advice that contains ("bottle") AND ("baby" OR "toddler"), all results will show either baby and bottle OR toddler and bottle. You learn something new everyday.