text
To search the database, enter text into the box and hit the search button. A list of pages will be returned containing any of the words you've entered - each word will be a distinct search term. The default boolean operator is OR.

"text"
If you'd like to use a search term that's more than one word long, you'll need to enclosed it in speech marks - entering ginger cats will find pages that relate to ginger or cats, whereas "ginger cats" finds pages that relate to ginger cats. In short, you're amalgamating several words into one distinct search term.

+
Continuing with our ginger cats example, if you wanted to find instructions on feeding them, you'd use:

"ginger cats" +feeding

If you omitted the +, you'd be looking for pages on either ginger cats or feeding - if you use a +, both terms must appear on a page. It's the boolean AND operation.

-
Similarly, you can use a minus sign to specifically exclude certain terms. To find information on feeding ginger cats, but that specifically don't mention the phrase tabby, you'd use:

"ginger cats" +feeding -tabby

It's the boolean NOT operator.

~
The tilde character (that's 'squiggle' to you and me) tells the search engine that you're looking for a search term to be relatively close to another. Forgetting tabbies for a moment, if you wanted to make sure that the word feeding turned up relatively close to the phrase "ginger cats", you use:

"ginger cats" ~feeding

It's the NEAR operator.