How to ignore offset in jekyll when previous post

i'm trying to create my first blog on jekyll. And i stucked in one stupid thing. so the theme is next: i have a section for one of my categories, let it be "news":

<section class="news">
    <div class="container">
        <div class="row no-gutters">

{% for post in site.categories.news limit: 2 offset: 0 %} 
{% include news-item-col-6.html %}
{% endfor %}

{% for post in site.categories.news limit: 3 **offset: 2** %}
{% include news-item-col-4.html %}
{% endfor %}

        </div>
    </div>
</section>

news-item-col-6:

{% if post.thumb != 0 %}
   <div class="col-md-6">
        <div class="pattern">
            <div class="overlay item-title" style="background-image: url({{ post.thumb }});">               
                <div class="item-title-content">
                    <h3><a href="{{ post.url }}">{{ post.header }}</a></h3>                     
                </div>
            </div>      
        </div>
    </div>
{% endif %}

news-item-col-4:

{% if post.thumb != 0 %}
  <div class="col-md-4">
    <div class="pattern">           
        <div class="overlay item-title" style="background-image: url({{ post.thumb }});">
            <div class="item-title-content">
                <h3><a href="{{ post.url }}">{{ post.header }}</a></h3>                 
            </div>
        </div>                  
    </div>
  </div>
{% endif %}

my posts tp

---
layout: post
title: title | site.com
header: title
description: discription
categories: categories url
catname: News
image: "images/URL /to image/1.jpg"
thumb: "images/URL /to thumb/1t.jpg"
permalink: "blog/:categories/:year-:month-:day-:slug.html"
---

so the problem is that not all of my posts will have background thumb, and all i want to do is to ignore the posts wich has no {post.thumb}. and the code is works, but unfortunately col-md-4 block's offset is not ignoring post's order with no post.thumb.

in picture bellow ill try to explain what i want:

This is how schould be, if all my posts have post.thumb(bg_image)

This is how should be, if my post Item2 has no post.thumb(bg_image), it just not showing up in section

And this is how my code works :D

so what a should do to make it works right?

P.S. My english is bad enough, so im sorry for grammar mistakes and i`m assking u guys to give answers as much simpple as u can do...

Just use a custom counter, like this:

{% assign counter = 0 %} <!-- create a custom counter and set it to zero -->
{% for post in site.categories.news %} <!-- loop through the posts in news -->
  {% if post.thumb %} <!-- check if the post has a thumbnail -->
    {% assign counter = counter | plus: 1 %} <!-- increment the counter if it does -->
    {% if counter < 3 %} <!-- if this is the first or second counted post -->
      {% include news-item-col-6.html %} <!-- include the col-6 element -->
    {% elsif counter < 6 %} <!-- else -->
      {% include news-item-col-4.html %} <!-- include the col-4 element -->
    {% endif %}
  {% endif %}
{% endfor %}