If the search words are not in the page name, they check to see if the page title matches any of the search words. Next they check the relevancy of the search words compared to the context on the page. Finally they check the search words in comparison to the meta tags. However, a few search engines place a higher priority on meta tags than on the context. There are so many websites that will have a relevancy to most search words, that you don't stand a chance of being seen unless the search words are at least in your page title.
Many search engines hate punctuation marks.
There is one exception to this. It is used to separate key phrases. Do not go any further into subdirectories than absolutely necessary. Search engines don't like subdirectories. The more you divide your website into subdirectories of subdirectories, the more likely the search engines will not pick up the pages.