Scenario: You read a 2007 article by Linhares and Brum that cites an earlier article, by Klein. You want to cite Klein's article, but you have not read Klein's article itself.
Linhares, A., & Brum, P. (2007). Understanding our understanding of strategic scenarios: What role do chunks play? Cognitive Science, 31(6), 989-1007. https://doi.org/10.1080/03640210701703725
Your Reference list will contain the article you read, by Linhares and Brum. Your Reference list will NOT contain a citation for Klein's article.
Klein's study (as cited in Linhares & Brum, 2007) found that...
Your in-text citation gives credit to Klein and shows the source in which you found Klein's ideas.
See Publication Manual, p. 258.