Now let's look now at some ways to increase our results.  We found that adding another concept with the word "and" decreased our results. 

Adding another concept with the word "or" increases our results.  That is because it gives the computer a choice:  match this term or that term, so more articles meet the criteria.

Let's try it.  In the Find box below, type:  instant messaging or text messaging.  Click on the Search button.