Search for cases using keywords or the title. Note that the search results will include documents from Harvard Business Press Core Curriculum, which provides access to readings that cover entrepreneurship, finance, accounting, marketing, operations management, organizational behavior and strategy. To make sure you're looking at HBS cases, look for HBS Case Study Collection in the results list:
In addition, you can find some Harvard Business School case studies in Business Source Premier. Harvard Business Review publishes one case study per issue. In the advanced search, select Full Text, enter Harvard Business Review under Publication, and select Case Study under Document Type. See image below.
You can find cases on the tech sector using IDC. To search for case studies, enter "case study" in the search box on the main page. You can then use the filters on the left side of the search results page to narrow down the case studies based on audience (tech supplier or tech buyer), document type, topic or region.
Search the following databases to find articles dealing with your particular topic (e.g., employee empowerment and airlines). You can search specifically for case studies in some databases. From the advanced search in both ABI/Inform and Business Source Premier, you can select "case study" under document type.