Although SciFinder is a diverse, complicated database, there are numerous tutorials and guides prepared by CAS to help you navigate.
For example, a research topic search on caffeine and blood sugar:
Yields results more than 7,000 results. The results list provides a list of articles, proceedings, and other literature, with abstracts, relevant to the topic. Filters for narrowing down your search further to document types, authors, and substance roles are easy ways to find more valuable resources to you. In addition, the number of times each article has been cited, an indicator of its importance, is provided. Unlike most databases, SciFinder also links to substances and reactions associated with the topic.