Sure. You can do this by creating a role, say, "security_personnel", assigning search term restrictions to that role and then finally adding the users you want to that role. In the web UI under Manager >> Access controls >> Roles >> (your chosen role), there is a field called "Restrict search terms" that you can use to add whatever restrictions you want for that role. These search terms will be implicitly added to any search that users of this role issue.
More information on users and roles is available in the Admin manual here: http://www.splunk.com/base/Documentation/latest/Admin/Addusersandassignroles
