It is not enough to randomly type in all possible search terms. To find specific and targeted information about your subject, you need to combine search terms. There are various techniques for doing this:
Boolean operators
Truncation
Phrase search
Boolean operators
With the Boolean operators AND, OR and NOT, you can combine search terms, search for multiple terms at once or exclude certain terms.
AND
The AND operator allows you to combine search terms. If you use AND between two search terms, the database will only show results that contain both words.
The search result will be limited, smaller than when searching for a single word.
Example: you are looking for information about the relationship between obesity and food in canteens: obesity AND canteen AND food
OR
The OR operator ensures that you find results that contain one word or the other, or both. Useful for synonyms, abbreviations and related terms. Please note: Search terms combined with OR must always be placed in brackets.
The search result is enlarged and expanded compared to searching for a single word.
Example: in addition to canteens, you also want to search for school canteens: (canteens OR "school canteens")
NOT
The NOT operator allows you to exclude results.
The search results will be reduced, but be aware that you may also miss relevant information.
Example: you want information about canteens in schools, but not about canteens in primary schools: schools NOT "primary schools"
Please note!
Always type AND/OR/NOT in capital letters.
If you combine multiple Boolean operators, put the OR terms in brackets. Example: (canteens OR "school canteens") AND obesity. If you do not use brackets here, the AND command will only work for "school canteens" and obesity.
In Google you can use OR as described above, is AND enabled by default, and you must use a minus sign (-) for NOT.
Truncation
Truncation is replacing part of a word with a wildcard character. This means that you search for words beginning or ending with the word you typed. The manual for the database you are searching in will indicate which character is used for this. This is often an *. Other possible truncation characters are a ? or !.
If you place a truncation character after a word or part of a word, you will search for what you have typed and everything that can follow. Example: pig* returns: pig, pigs, etc.
If you place a truncation character before a word or part of a word, you will search for what you have typed and everything that can come before it. Example: *rose gives: rose, primrose, etc.
If you type a truncation character in a word, you will search for multiple spelling variations. Example: colo*r gives: color or colour.
Tips!
The trick is not to truncate too early or too late. If you are looking for information about 'pollution', type pollut* and not poll*.
Truncation does not work in Google.
Phrase search
If you are searching for an exact word combination or a term consisting of multiple words, place it in double quotation marks (""). If you do not use the double quotation marks, you will receive a lot of search results that are not relevant. Examples: "European directives", "Rotterdam University of Applied Sciences", "climate change".