Nuthab.com is the address of a fake search engine. As such, it cannot produce results on its own. Any search query initiated via this engine will be redirected through the legitimate Yahoo engine for the results shown to the user. Knowing this, it wouldn't seem that surprising that users are extremely unlikely to use Nuthab.com willingly.
No, fake engines have other tactics to force themselves into the users' Web browser via so-called browser hijackers s, mainly. These PUPs (Potentially Unwanted Programs) are designed to take over Web browsers and modify their settings specifically. The goal is to then drive as much artificial traffic towards the promoted fake engine as possible. Nuthab.com is not an exception, as it also is promoted via an associated browser-hijacker application.
Affected users will notice that the usual homepage, new page tab, and default search engine have all been set to now open the Nuthab.com address. Furthermore, the PUP might have persistence mechanisms already established on the system that ensure its presence. Subsequently, any attempts to revert the modified settings to their original states will be blocked by the browser hijacker.
Users also should be warned about the likelihood of Nuthab.com monitoring their browsing activities. The targeted information includes all visited URLs, opened pages, conducted searches and more. The acquired information could be used to determine certain personally identifiable details, IP addresses, etc. The data is then transmitted to a remote server, where the operators of the PUP can decide to exploit it in a variety of ways, including sharing/selling it to third parties.