Selecting two fields at once in Laravel?

Question

Laravel

I have a table with the following structure

id
sell_user_id
buy_user_id

Please tell me how to make a request so that all data in which, for example, sell_user_id = 1 and buy_user_id = 1, are included in the selection, and if sell_user_id = buy_user_id, then two fields were created.
Now I am doing with the orWhere method

$trades = $trades->where(function($query) use ($request) {
    $query->where('trades.sell_user_id', $request->user()->id)->orWhere('trades.buy_user_id', $request->user()->id);
});

but if sell_user_id = buy_user_id, then only one field comes into the result.