I searched for “libreoffice calc pivot table”. In DuckDuckGo and Google, the very first result is “Chapter 8 Pivot Tables - LibreOffice”. Hooray, just what I want.
But the result URL is Chapter 8 Pivot Tables , i.e. a guide for version 7.1, an unsupported LO version last updated in 2021. You have to realize that you’re reading documentation for an older version of LibreOffice and that documentation for the newer version you’re probably using is available.
This is similar to bug 118235 that I filed, “obsolete LO wiki help pages dominate Google search results”. There were various suggestions in that for obsoleting old docs and/or de-emphasizing them in search results and/or putting an “older version” banner on them.