cane

var myArray = [
	  {id: 1, name: 'Вася', age: 21, city: 'Москва'},
	  {id: 2, name: 'Коля', age: 22, city: 'Новгород'},
	  {id: 3, name: 'Петя', age: 23, city: 'Челябинск'},
	  {id: 4, name: 'Саша', age: 24, city: 'Омск'},
	  {id: 5, name: 'Ваня', age: 99, city: 'Омск'}
	];
	
	function filterByCity(arr, city) {
		return arr.filter(function(item, i, arr) {
			  return (item.city == city);
		});
	};

	var omsk = filterByCity(myArray, 'Омск');

	console.log(omsk);