siteLevel supports the AND argument, or the + (plus) which requires the word be present in a document in order for it to qualify as a matching result.  In the example below, the words central, park, and the phrase "new york" must all be present in a document in order for it to show up on the results page.
 
 
 
The the example below, the words William and Jefferson must both be present in a document in order for it to show up on the results page.
 
 

NOT - (minus)

As important as it might be to require a word to exist in a search query, it may be just as important to provide words that you do not want to be present in a search.  This is where the NOT argument, or the - (minus) comes in handy.  This often helps visitors remove documents by specifying words that may not have relevancy to their search.  In the example below, the words central and park are required, however, the word mime must not be present in order for a document to show up on the results page.
 
 
 
The same thing can be accomplished with + and - operators in the example below.
 
 

 
OR | (pipe)

The OR argument, or the | (pipe) is a condition that states that the word or phrase can be present (and thus give it a higher relevancy ranking), but it is not required for a document to show up on the results page. This argument is useful to include additional search query parameters without completely removing other candidate matches.  In the example below, the word search is required, but the word term is not -- however, if it is present in a document, it will score a higher relevancy.
 
 

 
"phrase search"

Searching for phrases means that the words between the quotes must show up in that exact order, adjacent to one another.  In the example below, the complete phrase "Detroit Rock City" must be present in a document in order for it to show up on a results page.  Having the words Detroit, Rock, or City on the document is not enough -- the words must be in the exact word order as provided between the quotation marks.

 
Wildcard *

Searching with wildcards allows a query to search for a partial match of a word.  The conditions are that a wildcard can only appear at the end of a search term, and at least two characters must be provided before the wildcard * (asterisk) argument.  In example below, all matching documents that contain words that begin with the characters De and contain the word Miller will show up on the search results page:
 
 
 
Examples of words that satisfy the De* wildcard search term are: Detroit, Dennis, Dean, and Demolition.