What actually happens when you type in a keyword phrase into a search engine and click on the search button.
Lets take the example of what happens when the term, 'beauty salon' is searched on. How does the search engine find the pages in its index that it will return in the search engine results page (SERP)?
Generally, the search engine will look for the following: 
- pages that contain the exact phrase beauty salon
- pages that don't have the phrase beauty salon, but does have the words beauty and salon in close proximity
- pages that have the words beauty and salon, but not necessarily close together
- pages with word stems; for instance, pages with the words beauty and salon somewhere in the page
- pages that have inks to them , in which the link text contains the phrase beauty salon
- pages with links pointing to them, with the link text containing the words beauty and salon although not together

The search engine will not show results in the exactly the same order as described above. It will also take into account other considerations, such as: 
 | Is the keyword phrase found in bold text
|  | In italic text
|  | In bulleted lists
|  | In text larger than most of the other text on the page
|  | In heading text (<H> tags?)
|  | Is the domain extension the same as the county that the search originates from? i.e. a search for beauty salon from Google.ie may favour .ie sites
|  | In what country is the site hosted?
|  | How old is the site?
|  | What types of sites are linking in?
|  | What types of links are going out?
|  | ...and many other 'secret' criteria |

If a search engine can't relate to your website words that someone searches for, it has no reason to return your website as part of the search engine results page (SERP).
 Choosing the right keywords is critical

In order to choose the most powerful keywords you have to think like your customer and not what you think is most appropriate.  Implement a comprehensive keyword analysis and research strategy

Check to see what people are actually searching on 
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