Whenever you create, copy or move a file or folder, Windows Search Indexing feature scans the location in order to index all the contained items. The indexed items help speed up the search process. Once search index is built for all locations and saved items, Windows can provide you with search results instantaneously, as it no longer has to manually find the item from the specified location. The Windows search is basically responsible for retrieving and displaying the search results from the list of indexed items. The search index keeps running in the background as a Windows service named WSearch. Although it significantly speeds up the search process, it may consume significant system resources. While people who are using high-end PCs do not care about processes that consistently consume physical memory resources, users with slower computers can feel a difference in the response time while performing even routine tasks. Another reason for disabling the service is that if, for some reason, the indexed items are not being displayed correctly, turning it off and performing a cold reboot of your system can fix the issue. Read on to find out how to disable the search indexing service in Windows 8.
You can check whether the Windows Search service is running or not from Task Manager. You can stop the service by right-clicking it and selecting Stop, but it will open start running the next time you log into your PC.
To stop the service permanently, go to Start Screen, type in services.msc and hit Enter.
This will open the Services dialog box that contains all the local services associated with different Windows programs.
In the list, look for the service named Windows Search. Right-click it and select Properties from the context menu.
Under the General tab in the Properties dialog box, look for Startup Type. By default, it is set to Automatic (Delayed Start). Open the drop down list, select Disabled and hit OK to disable the Windows Search service.
The next time you log into PC, the service will not start automatically. It can be verified by heading over to the Services tab in Task Manager and looking for the WSearch service. Under Status column, you can check that the status of WSearch service is Stopped.
Source: How To Permanently Disable Search Indexing In Windows