After developing a research question, break it down into 2-4 words or short phrases. For example, if your research question was, "How will advances in consumer privacy impact the development of mobile phone applications in the future?", the keywords could be consumer privacy and mobile phones. From those two phrases, there is a better chance the database understands what you are searching for.
Head into a database. Enter your keywords into the search fields and click search. If you notice that there are too many results, you can always limit them by using the tools built into the database. For example, if you are searching within ScienceDirect, you can limit by article publication year or resource type, such as research articles or book chapters. This can help you better get to where you need to be to find relevant articles.
If your search results do not seem relevant to what you're looking for, pay attention to which words the database is using to describe different topics. After clicking on an article, you can scroll down to find which words the database developers have used to tag this article, based on general topics. By searching with those words -- possibly synonyms to your original keywords -- you'll have a better chance of finding relevant sources. Each database may use different terminology and ways of classifying the words. For instance, in ScienceDIrect, they're known as Keywords, but you might also see Subjects or Descriptors.
Found a relevant source for your topic? Be sure to check out its works cited or bibliography to find previously published articles that authors have cited that might also be relevant to your research. Sometimes, you can even click on each reference within the document and link directly to the cited article. If you find an article that isn't available through the library, you can always use Interlibrary Loan to request a copy or contact a librarian for assistance.