Download a list from storage with angularfire2

I can successfully save a document in firebase.

I would now like to display all the documents contained in a particular storage folder

But the documentation only specifies how to get a specific document:

@Component({
  selector: 'app-root',
  template: `<img [src]="profileUrl | async" />`
})
export class AppComponent {
  profileUrl: Observable<string | null>;
  constructor(private storage: AngularFireStorage) {
     const ref = this.storage.ref('users/davideast.jpg');
     this.profileUrl = ref.getDownloadURL();
  }
}

Finally i save the link doc in my database to retry the information.

SaveDoc() {
const Patientid = this.patientid;
    const name = Date.now().toString();
    const newDoc = new Doc(name, Patientid, this.url);
    console.log(this.url);
    this.docsService.CreatePpsDoc(newDoc);
}