How to get blog posts by label in blogger api

I using blogger api in my android app to integrate blogger content with it by using the REST APIs, as a JSON's objects.

I need to retrieve/filter posts by a label. In most blogs the link of blog's label it usually is

https://abtallaldigital.blogspot.com/search/label/Food
https://abtallaldigital.blogspot.com/search/label/Technology

I read all API documentation and I see it's deal with Blogs, Posts, Comments, Pages, Users but there's nothing to handle labels/categories in it.

There's a class BloggerAPI in the app that's used to retrieve blogs

package abtallaldigital.blogspot.com.dummyapp;

import retrofit2.Call;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
import retrofit2.http.GET;
import retrofit2.http.Url;

public class BloggerAPI {

    public static final String BASE_URL =
            "https://www.googleapis.com/blogger/v3/blogs/2399953/posts/";
    public static final String KEY = "THE-KEY";

    public static PostService postService = null;

    public static PostService getService() {

        if (postService == null) {
            Retrofit retrofit = new Retrofit.Builder()
                    .baseUrl(BASE_URL)
                    .addConverterFactory(GsonConverterFactory.create())
                    .build();
            postService = retrofit.create(PostService.class);
        }

        return postService;
    }

    public interface PostService {
        @GET
        Call<PostList> getPostList(@Url String url);
    }
}

It is used thus

  private void getData(){

    String url = BloggerAPI.BASE_URL + "?key=" + BloggerAPI.KEY;

    if(token != ""){
        url = url+ "&pageToken="+token;
    }
    if(token == null){
        return;
    }

   final Call<PostList> postList = BloggerAPI.getService().getPostList(url);
    postList.enqueue(new Callback<PostList>() {
        @Override
        public void onResponse(Call<PostList> call, Response<PostList> response) {
            PostList list = response.body();
            token = list.getNextPageToken();
            items.addAll(list.getItems());
            adapter.notifyDataSetChanged();
            Toast.makeText(MainActivity.this, "Sucess", Toast.LENGTH_LONG).show();
        }

        @Override
        public void onFailure(Call<PostList> call, Throwable t) {
            Toast.makeText(MainActivity.this,"Error occured",Toast.LENGTH_LONG).show();
            Log.i(TAG, "onFailure: "+t.toString());
        }
    });

}

I googling for how to get a link of RSS Feed for any label and I found this result

https://example.blogspot.com/feeds/posts/default/-/label/?alt=rss

this will gets the blog posts of any label with replacing the word "label" in the link