Ionic v4 searchbar

I am trying to add a search-bar to my list but I failed each time

my .html file

<ion-header>
  <ion-toolbar class="new-background-color">
    <ion-title>    
      <ion-text color="light">
        <h4> my app</h4>
      </ion-text>   

  </ion-title>
  <ion-buttons slot="start">
    <ion-menu-button autoHide="false" style="
    color: white;
"></ion-menu-button>
  </ion-buttons>
  
  </ion-toolbar>
</ion-header>

<ion-content>
    <ion-refresher slot="fixed" 
    (ionRefresh)="ionRefresh($event)" 
    (ionPull)="ionPull($event)" 
    (ionStart)="ionStart($event)">
      <ion-refresher-content
        pullingIcon="arrow-dropdown"
        pullingText="refresh"
        refreshingSpinner="circles"
        refreshingText=" ،،،Refreshin>
      </ion-refresher-content>
    </ion-refresher>
    <div style="
    align-content: center;
    justify-content: center;
    align-items: center;
    height: 50px;
    background-color: #3357a7;
    font-size: large;
    font-weight: bold;
    color: #ffc95b;
    margin-bottom: 10px;
    margin-top: 10px;
    text-align: center;
  ">
  
      <ion-label style="
      margin: auto;
      position: absolute;
      top: 30px; left: 0; bottom: 0; right: 0;
      
      ">  
        all content
        </ion-label>
        
    </div>
    <div style="
    align-content: center;
    justify-content: center;
    align-items: center;
    font-size: large;
    font-weight: bold;
    margin-bottom: 10px;
    margin-top: 10px;
    text-align: center;
  ">

        
    </div>
    
  


    <ion-grid class="mygrid">
      <ion-row class="my-item" *ngFor="let item of dataArray;let i=index" (click)="gotoNext(i)">
        <ion-col size="4">
            <ion-thumbnail>
                <img src="https://qateef-ads.co/uploads/{{ item.document }}" alt="your image">
            </ion-thumbnail>
        </ion-col>
        <ion-col size="6">
            <ion-row class="myitems">
              <p><strong> {{ item.title }} </strong>  </p>
              </ion-row>
              <ion-row size="6" class="myitemsc">
              <p> {{ item.city }} </p>
              <p  class="myitemstime"> {{ checktime(item.time) }} </p>
              </ion-row>
        </ion-col>
      </ion-row>
    </ion-grid>


  </ion-content>



my .ts file

import { Component, OnInit } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Router,NavigationExtras } from '@angular/router';
import { LoadingController } from '@ionic/angular';
import  * as moment from 'moment';

@Component({
  selector: 'app-tab2',
  templateUrl: './tab2.page.html',
  styleUrls: ['./tab2.page.scss'],
})
export class Tab2Page implements OnInit {
  dataArray;

  constructor(private http: HttpClient,private router: Router,public loadingController: LoadingController) {
   
}

      async ngOnInit() {
	   const loading = await this.loadingController.create({
      message: 'working....'
    });
    await loading.present();
        this.http.get('https://mysite.co/apis/all.php').subscribe(async (response: any) => {
		  await loading.dismiss();
          console.log(response);
          this.dataArray = response;
		 
      });
  }

 
  async ionRefresh(event) {
   const loading = await this.loadingController.create({
      message: 'working....'
    });
    await loading.present();
    console.log('Pull Event Triggered!');
    this.http.get('https://mysite.co/apis/all.php').subscribe(async (response: any) => {
	 await loading.dismiss();
      console.log(response);
      this.dataArray = response;
      event.target.complete();
  });
}

gotoNext(index) {
  localStorage.setItem('detail', JSON.stringify(this.dataArray[index]));
  this.router.navigate(['/details']);
}

ionPull(event) {
  console.log('ionPull Event Triggered!');
}

ionStart(event) {
  console.log('ionStart Event Triggered!');
}
checktime(dttime)
{

return moment(dttime).fromNow().toString();
}

}