How to Search Listview (Json data) through Searchbar in xamarian.forms ?

This is my updated project, i'm able to display data (json) through Api in the ListView but i am not able to filter that data through Search bar. I tried lots of thing but i can't solve. So can any one please solve my problem. Im new in this field #Thanks.

I tried this link:-

                   https://www.syntaxismyui.com/xamarin-forms-searchbar-recipe/

                   https://blog.verslu.is/xamarin/finding-nemo-implementing-xamarin-forms-searchbar/

NewsFeedPage.cs:->

using System;
using Xamarin.Forms;
using System.Collections.ObjectModel;
using System.Net.Http;
using Newtonsoft.Json.Linq;
using System.Diagnostics;
using Newtonsoft.Json;
using System.Collections.Generic;

namespace Searchbarr
{

public class NewsFeedPage : ContentPage
{

    public static ObservableCollection<string> items { get; set; }
    public NewsFeedPage ()
    {

        Title = "Searchbar";
        SearchBar sb = new SearchBar{ 
            Placeholder="Type here to search" ,


        };

        items = new ObservableCollection<string> ();
        ListView lstView = new ListView ();
        lstView.ItemsSource = items;

        //------------------------Get NewsFeed API----------------------//

        var client = new HttpClient ();
        client.BaseAddress = new Uri ("http://hallpassapi.jamsocialapps.com");
        var result = client.GetAsync ("http://hallpassapi.jamsocialapps.com/api/NewsFeed/GetNewsFeed?order_by=desc").Result;
        string resultContent = result.Content.ReadAsStringAsync ().Result;
        var bob = JObject.Parse (resultContent);
        var asd = JsonConvert.SerializeObject (bob["responselist"]);
        var questionsList = JsonConvert.DeserializeObject<List<Question>>(asd);
        foreach(var question in questionsList)
        {


            Debug.WriteLine("Question 3 "+question.Feed);
            items.Add (question.Feed);



        }

        Content = new StackLayout (){
            Padding = new Thickness (0, 35, 0, 0),
            Spacing = 3,
            BackgroundColor = Color.White,
            Orientation = StackOrientation.Vertical,
            Children = {
                sb,
                lstView,



            }

        };


    }

}

}

Another class:-

                Question.cs:->

using System;
using Xamarin.Forms;
using System.Collections.Generic;
using System.Net.Http;
using Newtonsoft.Json.Linq;
using System.Diagnostics;

namespace Searchbarr
{
public class Question
{

    public string Feed { get; set;}

}

}