In this article on IJNet, Juan Pablo Marín Díaz, founder of data journalism portal Datasketch, explains why it's important for reporters to be able to collect and combine small data sets to find stories. He points out that even in the case of a large investigation such as Panama Papers, where the leaked information was around 2.6 terabytes, the final data that was used was a "collection of small data files".
Díaz suggests using a site like data.world or Statista to access smaller, open data sets, and keeping an eye out for information compiled by members of the public which can help "engage with readers and find interesting topics for stories".
When it comes to illustrating your information, he recommends using point-and-click data visualisation tools such as Datawrapper or Flourish which allow you to create charts and interactive elements for your story.
"Unraveling truths requires pulling together multiple sources of information and organising them into smaller chunks that comprise a story. For any data-driven piece, each source could be a path to explore a unique story."