AND
, OR
, and NOT
work to refine your search results.- AND: Use this when you want to find documents that contain all the search terms you're querying. For example, if you search for
global AND warming
, you'll only get results that include both terms. - OR: This is useful when you're looking for any one of several terms. Searching for
virus OR bacteria
gives you results that mention either term. - NOT: This operator excludes terms from your search. If you search for
smartphone NOT Apple
, you'll get results for smartphones that do not mention Apple.
AND
takes precedence over OR
. It's like multiplication and addition in arithmetic: multiplication comes before addition, just as AND
comes before OR
in search operations.For more complex searches, you can use parentheses to group terms and operators. This is similar to using parentheses in math to control the order of operations.
- Using Parentheses: If you search for
(earthquake OR tsunami) AND Japan
, the search engine looks for documents that mention eitherearthquake
ortsunami
along with the termJapan
. However, if you don't use parentheses, as inearthquake OR tsunami AND Japan
, the engine will first find all documents that mentiontsunami
andJapan
, and then include all documents that mentionearthquake
, whether or not they mentionJapan
. - Nested Parentheses: If you have a search like
((renewable OR solar) AND energy) NOT oil
, the search engine first processesrenewable OR solar
, then addsAND energy
, and finally excludes any results that includeoil
. - Phrase Searching with Booleans: If you put a Boolean operator inside quotation marks, like
"cats AND dogs"
, the operator is ignored because the search engine treats it as a phrase to search for exactly as it is. - Using the Wildcard "*": When you want to expand your search to include various suffixes of a word, use the asterisk (*) as a wildcard character. For example, if you search for environ* AND protection, the search engine will retrieve documents that contain any words starting with "environ" (such as environment, environmental, or environmentally) in conjunction with the word "protection". This allows for a more comprehensive search when you are looking for documents that may use variable endings of a particular word stem.
- When entering Boolean operators, it is crucial to type them in UPPERCASE letters. The system is designed to only recognize operators such as AND, OR, NOT when they are in ALL CAPS. This ensures the proper execution of your search queries.
Add Fields" feature is a functional component that enables end users to enhance and refine search queries. This capability allows users to dynamically add additional criteria to their searches, thus providing a means to specify and narrow down the results according to their unique requirements. From an end-user perspective, it offers a customizable search experience where one can incrementally include parameters beyond the default options, allowing for more precise and relevant outcomes. This feature supports efficient retrievals by minimizing noise and improving the accuracy of the search results. It directly contributes to a more effective and satisfying user experience by aligning search results more closely with the user's intent. Additionally, it empowers users by providing them the flexibility to manipulate the breadth and depth of their search criteria without overwhelming them with options upfront.