Why does "Full Text Search" take a lot of time in SDL MultiTerm 2019 - 15.0.1.43891?

SDL MultiTerm 2019 - 15.0.1.43891 has been taken a lot of time when using "Full Text Search" (Hierarchical or Parallel or Sequential Mode), showing the Windows' rotating ring, and then it is shown "not-responding".
 
The Termbase file (Source Language: English-USA - Target Language: Portuguese-Brazil) has been reorganized several times per day (and it does not show any defective entry or empty entry), and the Termbase file is installed locally (on my internal hard drive C:), i.e. in c:\Users\renato\Documentos\SDL\SDL MultiTerm\Termbases\ [the same drive c: where SDL MultiTerm 2019 Desktop is installed ("C:\Program Files (x86)\SDL\SDL MultiTerm\MultiTerm15\MultiTerm.exe") in Windows 10 Pro 64 bit.
 
The SDL MultiTerm 2019 - 15.0.1.43891 was uninstalled, and reinstalled again, correctly, using the "SDL MultiTerm 2019 CU1 Desktop Installer" file, that was downloaded from the site oos.sdl.com/.../mydownloads.asp
 
Is it a defect from SDL MultiTerm 2019 - 15.0.1.43891?
 
Thank you very much for your kind attention,
Best regards,
Renato Colonna Rosman