Boolean searching is one of the most important and widely used methods used to search for articles in databases. There are opportunities to focus or broaden your search depending on how you use the Boolean Operators AND, OR, NOT.
Figure 1. How Boolean operators work.
Example Search 1. The researcher wants to know about programs that assist teenagers to stop smoking.
1. Concept 1. Search health promotion OR health education
2. Concept 2. Search adolescent OR adolescence
3. Concept 3. Search smoking cessation
4. Lastly combine all three of the above searches with AND.
Each concept can be search separately then combined in a separate search as in Screenshot. 1
Alternatively, the search can be written as one sequence, where brackets group the synonyms and ensure that the search is carried out in the correct order as in Screenshot 2.
(health promotion OR health education) AND (adolescent OR adolescence) AND smoking cessation
2. Applying filters/limiters
Applying filters/limiters at the end of the search is recommended.
The best method is to use the edit search button and use all useful limiters on the screen.
Alternatively use the left hand filters panel although not all filters and limiters are available.
3. Apply truncation/substitution (these tend to increase the numbers of your search results.)
3.1 The wildcard (Substitution) is represented by a ?or # in CINAHL.
For example, type ne?t to find all citations containing neat, nest or next.
Use the # wildcard in places where an alternate spelling may contain an extra character. For example, type h#ematology to find all citations containing haematology or hematology.
3.2. Truncation is represented by an asterisk (*). To use truncation, enter the root of a search term and replace the ending with an * (asterisk).
For example, type nurs* to find the words nursing, nurses, nurse, or nurseries,
Also using the earlier example in Search 1: adolescen* will retrieve adolescent and adolescence.
3.3 Note: The Truncation symbol (*) may also be used between words to match any word. For example negative pressure * therapy will return results that include the exact phrase, negative pressure wound therapy.
4.Field searching. Search for an author in the author field and/or a keyword in the title field to quickly locate a paper that you may have seen in a reference list in a textbook or possibly in another research paper.
5. Using Subject headings in CINAHL.
Each article in a database like CINAHL (and also MEDLINE) is read and assigned several subject headings. The subject headings describe the main concepts in the article. By using the subject headings your search is improved it 'standardises' variation in terminology and language . for example: hypertension or high blood pressure.
In CINAHL , Medline and PubMed there are thousands of terms available. Subject groupings are arranged hierarchically. This hierarchical organisation of subject headings is sometimes referred to as a tree. The headings can also be referred to as MESH (Medical Subject Headings).
Phrase searching.
When a phrase of two words or more is used to search an EBSCO database, the default setting is for the words to be searched for within 5 words of each other . To search for the exact phrase, use inverted commas around the phrase.
Proximity searching is a way to search for two or more words that occur within a certain number of words from each other. 
As shown in the screenshot, topical AND collagen give the greatest number of results because the words are searched independently not as a phrase. The phrase search "topical collagen" retrieved least results. The proximity operators N5 to N10 (N meaning Near) retrieve an intermediate number of results.
Not all records have the full text attached therefore sfx software tries to find full text in other Holmesglen databases. If the full text is not available then a Google Scholar search is offered. If the full text of an article is present in another Holmesglen database then direct links to the article in other databases are given.
