In mutual fund investing, what are small cases and how are they different from thematic schemes?

"Small cases are a basket of stocks or ETFs, picked by financial experts after thorough research. These stock portfolios are basically thematic investments grouped together to track a sector’s growth."

from Wealth-Economic Times https://economictimes.indiatimes.com/wealth/invest/in-mutual-fund-investing-what-are-small-cases-and-how-are-they-different-from-thematic-schemes/articleshow/80324782.cms