Windows 10 has some quirks. After some updates, you find changes in the user interface and may eventually find that the search that opens when you press the Windows button or the power user key combination (Windows Button + X then Search). It used to be that you could open the Task Manager (Ctrl + Alt + Del or Ctrl + Shift + Esc), you could look for Cortana and kill it (Right-click, select "End Task"). But now no more. Cortana seems to have disappeared from the Task Manager. But a search online reveals that Cortana is not gone, just renamed. You now need to look for "Search" in the Task Manager. Kill this process. In its place a new process called "Search and Cortana Application" will be loaded as shown below. Perhaps someone need to write a tiny little app to carry out this simple task of killing "Search" and forcing Cortana to relaunch properly. Once you do this, Windows 10 search is now well behaved.