Phrasing a Serious Search

Sometimes, in order to phrase a very specific search, you need multiple words. And when you use multiple words, you might need to use operators to control the way a search site works with those words.

In mathematics, an operator is a word or symbol used to specify the action in an equation, such as plus or minus. Operators are used in search terms to express a logical equation of sorts that tightly controls how a search engine handles the term .

Using Multiple Words in a Search Term

In a search you can use as many words as you need in order to make the term specific.

For example, suppose I want to learn about boxer dogs. I could use the search term boxer . Although that term might turn up some hits about boxer dogs, those hits may be buried among hundreds of other links about prizefighters, China's Boxer rebellion, Tony Danza (actor and ex-boxer), and people named Boxer. So to make my search more specific, I use two words:

boxer dog

Now the search engine will look for pages that contain both "boxer" and "dog," which greatly increases the chances that hits will be about boxer dogs, because most pages about all those other "boxers" I mentioned earlier will not also be about "dogs." I still might see a link to a page about George Foreman's dog, if he has one. But the hit list will be a lot closer to what I want.

If my hit list is still cluttered with the wrong kind of pages, I might remember that a boxer is a breed of dog, so a page about boxer dogs probably also uses the term "breed" prominently. So I might try a third term to further narrow the hit list:

boxer dog breed

Get the idea? Now, if you get too specific, you might accidentally omit a few pages you want ”there might be boxer dog pages that don't use "breed" anywhere that would show up in a search database. So it's best to start off with a happy medium (a term that's specific but not overly restrictive ), see what you get, and then try subsequent searches using more or less specific terms, depending on what's in the hit list.

A few search engines support natural language queries . In a natural language query, you can phrase your search term as you might naturally phrase a question; for example, you might use the search term Who was the artist Leonardo da Vinci , and the search site applies sophisticated technology to determine what you're asking.

Natural language queries are a good idea, and they're worth experimenting with. But in my experience, their results are usually not as good as you would probably get with a really smartly phrased search term.

Using Operators to Control Searches

Whenever you use multiple words, you're using operators, even if you don't know it. Operators are words you use between the words in a multi-word search term to further define exactly how the search site will handle your term. Using operators in this way is sometimes described as Boolean logic . There are three basic operators used in searching:

• And ” When you use and between words in a search term, you tell the search engine to find only those pages that contain both of the words ”pages that contain only one or the other are not included in the hit list.

• Or ” When you use or between words in a search term, you tell the search engine to find all pages that contain either of the words ”all pages that contain either word alone, or both words, are included in the hit list.

• Not ” When you use not between words in a search term, you tell the search engine to find all pages that contain the word before not, and then to remove from the hit list any that also contain the word following not.

Table 13.2 illustrates how and, or , and not affect a search site's use of a term.

Table 13.2. How Operators Work in Search Terms

Search Term	What a Search Tool Matches
Dodge and pickup	Only pages containing both "Dodge" and "pickup."
Dodge or pickup	All pages containing either "Dodge" or "pickup," or both words.
Dodge not pickup	All pages that contain "Dodge" but do not also contain "pickup." (This gets all the Dodge pages, and then eliminates any about pickups.)
Dodge and pickup and models	Pages that contain all three words.
Dodge or pickup or models	Pages that contain any of the three words.
Dodge not Chrysler	Pages that contain "Dodge" but do not also contain "Chrysler." (This gets all the Dodge pages, and then eliminates any that also mention Chrysler.)

Before using operators in search terms, check out the options or instructions area of the search site you intend to use (see Figure 12.17). Most search sites support and, or , and not , but some have their own little quirks about how you must go about it. For example, Excite and AltaVista prefer that you insert a plus sign (+) at the beginning of a word rather than precede it with and .

Figure 12.17. Click the Advanced Search link near Yahoo!'s search term box to learn how Yahoo! supports operators and other advanced search techniques.

Another powerful way to use multiple words is to do an exact phrase match , which most search sites support. In an exact phrase match, you surround the multi-word term with quotes to instruct the search to match only pages that show the same words as the term, in the same order.

For example, suppose you want to know about the film Roman Holiday . A search on Roman Holiday will probably match any page that uses both of those words anywhere, in any order, together or separately. That'll still get you some good hits, but a lot of bad ones, too. A search on "Roman Holiday" (in quotes) matches only pages that use the exact phrase Roman Holiday, so the hit list will be much better targeted to what you want.

When you use multiple words and don't include operators, most search engines assume you mean to put "and" between words. (See, you are using operators, even if you don't know it.)

For example, if you use the term candy corn , most search engines assume you mean "candy and corn" and match only pages that contain both words.

Some engines will apply and first, and then use or . The "and" hits go to the top of the hit list, and the "or" hits go to the bottom, as lower-rated hits.

Conducting a Super Search

In high school, they warned you that you'd need algebra one day. If you ignored that warning (like I did), then you've forgotten all of that stuffabout grouping parts of equations in parentheses.

If you remember algebra, then note that you can apply those techniques for super searches. For example, suppose you wanted to find pages about pro boxers (the kind that hit each other). You would need a hit list that matched all pages with boxer or prizefighter , but eliminated any that matched dog (to weed out the boxer dog pages). You could do that with either of the following algebraic terms:

(boxer or prizefighter) not dog

(boxer not dog) or prizefighter

If you can apply these techniques, drop your old math teacher a note of thanks for a job well done.