Based on the symptoms, I guess that you have a different issue.
I too am using Digikam on Windows 10 (with 12 Gb Ram). I am finding not only that Digikam 8.2 freezes during during searches but also the Map search function closes if I attempt to use it.
I went back to V8.1, which was working prior to the installation of v8.2 and this solves the problem.