A story theme might be difficult to figure out because it is rarely stated explicitly.
A theme in a story is an idea that the writer keeps on repeating in his work. However, a theme in a story isn’t something stated in words, but rather it’s something you get to determine on your own while reading the story. The theme of a story is the universal idea that can be deduced by reading the story and understanding the basics of the characterization, plot and other literary elements that are included in the story.