The main concentration camps and estimates of the numbers murdered from each country. Image from Credo Reference.
Hunting Eichmann by
The CSS Library still keeps the five volumes list of subject headings (called the "red books") in a dictionary stand across from the circulation desk. Browsing the print books is sometimes easier than using the online version, but you can search the red books online.
If you aren't familiar with LC subject headings (and most people aren't) than can seem clunky & stilted. But, what they are trying to do is describe all the world's knowledge with the same precision as anatomists have described every part of the human body. It's just that words are slippery, and often have more than one meaning. The LC system is not perfect, but the alternative is no system.
LC used "Holocaust victims" for the stories of people who died during the Holocaust; "Holocaust survivors" for lives after the war of people who survived the Holocaust; and for the stories of the Holocaust by people who survived it, LC uses the subheading "personal narratives." Subject headings can also be narrowed by a geographical sub-heading. So, for the stories of the Holocaust in Poland by people who survived it, you would use -
Holocaust, Jewish (1939-1945) – Poland – Personal narratives
Seeing the organization of LC works best in large catalogs such as WorldCat. And easy way to start to access subject heading is presented in the section to the middle column - "make user of the bibliography."