Computers and the Internet have made  researches quick and easy. Just write a few words and … results are obtained rapidly!
But computers only search the word, not the idea behind that word.
The same idea can be expressed by different words, so the words you use during a search should be chosen carefully because they will have consequences in the search results.

1.Set the topic of your search
2. Set the most important related  words to your topic
3.Select the keywords you will use in your search

To define the keyword try to:

• use general or specialized  dictionaries and thesaurus. See
• gather descriptors and keywords used in papers of key publications.
• use thesaurus, list of keywords, phrases or vocabulary from several databases.
• use relevant databases to your study area and do some quick searches. Through these searches identify new keywords / synonyms / related terms.
• pay attention to keywords and descriptors used by indexers to the results provided by the databases you used.

Difficulty in defining the keywords?
Think of the keyword in a broad, restricted and related way

Example:university students
Broad: Pupils / Students
Restricted: medicine pupils  / medical students
Related: Youth / Young adults, Pupils in higher education / higher education students

1. You don’t  get any results?
Check the spelling. If all words are spelled correctly, try to use different keywords (synonyms).

2. The results are not adequate?
Try to use and / or to combine different keywords OR search in other databases.

And do not be afraid to ask help from your librarian!