Dacoity, Robbery, Life Kill Threaten

Dear Sir/Madam, Mrs "A" has present address is (sasural) in Odisha and permanent address is in Bihar and recently an occurrence happened in her Bihar address that some known people did docaity and robbery of RS 5:lakh including gold silver ornaments in her closed house of Bihar and FIR not taken by Police and same hss been sent via speed post and copy to SP and same has been delivered but no one taken any legal action or investigation and nor arrest done against accused people as well house is occupay forcefully and threaten life kill if we enter my house. so please let me know what have to do next against accused people. can I FIR or file case in my present address? it is legally acceptable. And requesting to all of you please guide me and advice with your legal advice at earliest. Thanking you with regards MD Sakil mob-09124088821