Потеря данных при вызове route.navigate

import {Injectable} from "@angular/core";
import {HttpClient} from "@angular/common/http";
import {Observable, BehaviorSubject} from 'rxjs';
 
 
@Injectable()
export class TopicService {
    topics: Observable<any[]>;
    private baseUrl: string;
    private _topics: BehaviorSubject<any[]>;
    private dataStore: {
        topics: any[]
    };
 
    constructor(private http: HttpClient) {
        console.log('constructor called');
        this.baseUrl = 'http://api.stackexchange.com/2.2/';
        this.dataStore = {topics: []};
        this._topics = <BehaviorSubject<any[]>> new BehaviorSubject([]);
        this.topics = this._topics.asObservable();
    }
 
    getData() {
        this.http.get<any>('someurl')
            .subscribe(data => {
                this.dataStore.topics = data.items;
                this._topics.next(Object.assign({}, this.dataStore).topics);
            }, error => console.error(error));
    }
}

import {Component, EventEmitter, Input, OnInit, Output} from '@angular/core';
import {TopicService} from "../services/topicService";
import {Observable} from "rxjs";
import {Router} from '@angular/router';
 
@Component({
    selector: 'search',
    templateUrl: 'search.component.html',
    providers: [TopicService]
})
 
 
export class SearchComponent implements OnInit {
 
    topics: Observable<any>;
 
    constructor(private topicService: TopicService, private router: Router) {
    }
 
 
    ngOnInit() {
        this.topicService.topics.subscribe(topics => {
            if (topics && topics.length) {
                this.router.navigate(['/results'])
            }
        });
    }
 
    @Input() searchTerm: string;
 
    @Output() searchTermChange = new EventEmitter<string>();
 
    onSearchTermChange(model: string) {
        this.searchTerm = model;
        this.searchTermChange.emit(model);
        this.topicService.getData();
    }
}

import {Component, OnInit} from '@angular/core';
import {TopicService} from "../services/topicService";
import {Observable} from "rxjs";
 
@Component({
    selector: 'search',
    templateUrl: 'results.component.html',
    providers: [TopicService]
})
 
 
export class ResultsComponents implements OnInit {
    constructor(private topicService: TopicService) {
    }
 
    ngOnInit() {
        this.topicService.topics.subscribe(topics => {
            console.log(topics); // [] empty array
        });
    }
}