Search techniques
Introduction
This section describes some important methods you can use to search efficiently and effectively. It gives you guidance on:
- using symbols to search for alternative word endings and spellings
- combining your concepts in a search statement
- searching for phrases
- performing more specific searches
Contents
- Truncation and Wild Card symbols
- Search operators
- Creating search statements
- Phrase and proximity searching
- Advanced search features
- Limiting searches by date, language or document type
Truncation and Wild Card symbols
Use to: widen your search and ensure that you don't miss relevant records
Most databases are not intelligent - they just search for exactly what you type in. Truncation and wild card symbols enable you to overcome this limitation. These symbols can be substituted for letters to retrieve variant spellings and word endings.
- a wild card symbol replaces a single letter - useful to retrieve alternative spellings and simple plurals
e.g. wom?n will find woman or women - a truncation symbol retrieves any number of letters - useful to find different word endings based on the root of a word
e.g. africa* will find africa, african, africans, africaans
e.g. agricultur* will find agriculture, agricultural, agriculturalist
Important hint! Check the online help screens for details of the symbols recognised by the database you are searching - not all databases use the ? and * symbols.
Search operators
Use to: combine your search words and include synonyms
Also known as Boolean operators, search operators allow you to include multiple words and concepts in your searches. The shaded areas on the diagrams below indicate the records retrieved using each operator.
- AND retrieves records containing both words.
- In this example the shaded area contains records with both women and africa in the text.
- It narrows your search.
- Some databases automatically connect keywords with and.
- OR retrieves records containing either word.
- In this example the shaded area contains records with women, or gender, or both words in the text.
- It broadens your search.
- You can use this to include synonyms in your search.
- NOT retrieves your first word but excludes the second.
- In this example the shaded area indicates that only records containing just Africa will be retrieved (not those with both Africa and Asia)
- Beware! By using this operator you might exclude relevant results because you will lose those records which include both words.
Creating search statements
Use to: combine multiple search words
On most databases you can type in a search statement, which involves combining your search words using search operators. When creating a search statement you must use brackets to ensure correct processing of the search.
- Words representing the same concept should be bracketed and linked with OR
e.g. (women or gender) - Groups of bracketed terms can then be linked with AND or NOT
This is an example search statement bringing together all the techniques described above:
(wom?n or gender) and agricultur* and africa*
Searches enclosed within brackets will be performed first and their results combined with the other searches.
This is how the search would look when entered into the CAB Abstracts database
Phrase and proximity searching
Phrase searching
Use to: make your search more specific
Phrase searching is a useful technique which can increase the relevance of your results. Sometimes your search may comprise common words which, when combined in an AND search, retrieve too many irrelevant records. Databases use different techniques to specify phrase searching - check the online help.
Some web search engines and databases allow you to specify a phrase using inverted commas.
e.g. "agricultural development"
e.g. "foot and mouth"
Hint! Some databases automatically perform a phrase search if you do not use any search operators e.g. agriculture africa is not a phrase used in English so you may not find any items on the subject. Use AND in between your search words to avoid this.
Proximity searching
Use to: make a search more specific and exclude irrelevant records
Some databases use 'proximity operators'. These enable you to specify how near one word must be to another and, in some cases, in what order. This makes a search more specific and excludes irrelevant records. For instance, if you were searching for references about women in Africa, you might retrieve irrelevant records for items about women published in Africa. Performing a proximity search will only retrieve the two words in the same sentence, and so exclude those irrelevant records.
Databases which have this facility vary considerably in their methods
e.g.: Web of Science - women same africa - retrieves records where the two words appear in the same sentence.
Hint! Check the online help for details of proximity operators recognised by the database you are searching.
Advanced search features
Many databases offer other more advanced features which you can use to refine your searches further. These techniques include:
- Search sets
Your results are displayed as "sets", which can be combined with other searches or new words. - Field-specific searching
Most database records are made up of different fields (e.g. author, title etc.). Field-specific searching allows you to select a particular field in which to search, rather than performing a keyword search across all fields. Some databases allow you to type words into specific search boxes, whereas in others you will need to type in the field name or its code.
Hint! Check help screens for field names or codes, and other hints on searching specific fields. - Searching using indexes
It is possible to search some databases using indexes, which are usually alphabetical lists of authors or subjects. They allow you to refine your search using the correct form of names or terms as defined on that particular database.
Hint! Not all databases allow searching using indexes. Check the online help on a particular database for more information.
Limiting by date, language or document type
Many databases allow you to limit your search in various ways. Limits are usually available on advanced search screens, or you can apply them after doing your keyword search. An example of the search limits from the CAB Abstracts database is shown on the left.
Check the help pages on the database you are using for detailed instructions on applying these limits.
Examples of the types of limits you can apply include:
- by date
- by language
- by publication type (e.g. journal articles, chapters in books, review articles that provide detailed summaries of research, book reviews)