Laravel: Query the models where the relationship is greater than 0

I'm doing a Laravel query to query a list of elements that his relationship is grater than 0.

The table concerts:

| ID |    NAME   |
|----|-----------|
| 1  | Concert A |
| 2  | Concert B |
| 3  | Concert C |

And the Position table.

| ID |  concert_id    |   user_id  | Content  |
|----|----------------|------------|----------|
| 1  |       1        |      1     |    xxx   |
| 2  |       1        |      2     |    yyy   |
| 3  |       3        |      1     |    zzz   |
| 4  |       3        |      2     |    www   |
| 5  |       1        |      3     |    xyx   |
| 6  |       3        |      3     |    rer   |

The query that I need to do is, get the concerts where their position has in the content a value like $some_query$.

The code I've is the following:

$result = $this->model->whereHas('positions')
    ->with(['positions' => function ($query) {
        $query->where('content', 'like', "%{$content}%");
    }])->get();

But as far as I can tell, this will bring all the concerts, and also this is going to bring only the positions that has the desired content.

So I've two problems, the first one is I need to get the concerts that his queried positions are greather than 0. And the second one is that also I need to bring all the positions, not only the queried ones. Basically the query is just a way to know which concerts I need to bring.

Is there possible to achieve this on a single query?

via Chebli Mohamed