[xwiki-users] How to the restrict the user name and group name serach?

Hi All, I dont want to allow the user name or group name search on xwiki(either it is on click of search button and search sugest). *Basically what i want is if any user put some user name or user group name in search text box , it should not return any results. Looking for your expert suggestion how i can go for it?* I am sure it should be possible in xwiki looking at its flexibility but could not figure it out how. Even if i have to make some modification in code iam open for that. Thanks in advance.