You can do remote viewing to find out where they are, but it is incredibly difficult to do it you have strong emotions about these objects returning (it can cloud your thought).
The better option is just to visualise these things regularly for a shott period of time, without thinking about them as « lost », and to then « forget about them ». The forgetting won’t mean you’ll never find these things, but it releases resistance so that they come back to you quickly – they will!