Searching databases for scientific work/ articles
Searching for articles on a topic is a skill that you get better at over time. Here are some tips to get started:


Ask your colleagues in your field which databases they use most commonly.  For instance, PubMed targets journals in the biosciences and medical fields.  PsychInfo indexes psychology journals, etc.
Google Scholar is a very capable tool, though the scope is typically broader than a more focused search engine.
Using a few articles you already have as starting points, review the reference list and pick out additional articles cited in the work that are of interest, then go read those, then repeat the process.  After time, you'll start to have an intuition on the authors, journals, and keywords that help you construct a search.
Use a 'cited by' search - first find a particular article you already have on your topic, then find the articles that cite that article. This can open up further routes for exploration.