var friends = {
    bill: {
        firstName: "Bill",
        lastName: "Gates",
        number: "0727 359 578",
        address: ['167','Riverside Drive','Kileleshwa','NA','00100']
        },
    steve: {
        firstName: "Steve",
        lastName: "Jobs",
        number: "0727 964 175",
        address: ['468','University Avenue','Palo Alto','CA','55544']
        }
    };

var list = function(x) {
    for (var key in friends) {
        console.log(key);
        };
    }

var search = function(name) {
    for (var key in friends) {
        if (friends[key].firstName === name) {
            console.log(friends[key]);
            //return friends[key];
            };
        };
    }

search("Steve")

______________________________________________
Result1:

{ firstName: 'Steve',
  lastName: 'Jobs',
  number: '0727 964 175',
  address: [ '468', 'University Avenue', 'Palo Alto', 'CA', '55544' ] }

Result 2:

First Name: Steve
Last Name: Jobs
Number: (408) 555-5555
Address: 1 Infinite Loop
         Cupertino, CA 95014