When you add alternative criteria separated by OR you increase the likelihood of finding documents that meet at least one of your criteria. For example, suppose you want to find press releases. Now your search will find documents that have either the phrase press release or the word announcement in the index. Using Individual Words Instead of Phrases You can widen your search by using individual words rather than phrases. You can increase your chances of locating the right document by searching for the words rather than the phrase.
Some words have more than one correct spelling.
For example, labor is correct in the United States, but labour is correct in the United Kingdom. And sometimes those who create documents misspell the title or keywords. If your search does not find what you are looking for, including the gramatically stemmed variations of your search criteria, you can still widen your results lists to account for spelling variations and misspellings by replacing some of the characters of the words in your search criteria with wild card characters.