In the new version 3.2 PDF indexing doesn’t index PDF text, only the PDF file names. In 3.1.2 this worked fine.
During installation did you switch on the option to index?
If you did not then uninstall and re-install with that option selected
If when opening
options it is not offered then you have the wrong installer 32bit will not work on 64 bit and vice versa.
My last test found searched text within contents worked when windows folder options is set to “Always search filenames and contents” for that folder
Helps to give versioning info e.g. platform win 10x64 and SumatraPDF help about version 3.2 or v3.2 x64
This type of issue is best raised at https://github.com/sumatrapdfreader/sumatrapdf/issues