Unit test orWhereHas,whereHas Conditions using fakers

I'm new to both unit testing, Fakers and laravel. I'm trying to unit test my resource controller, but I'm stuck at the serach function.

I would like to know how can I test "orwhere /orWhereHas .. " condition using unit testing and fakers

Here's my controller:

public function search(Request $request, Order $order)
    {
        $order = $order->newQuery();
        $order->with([
            'contact',
            'contact.company',
            'transport_order',
            'transport_order.driver',
        ]);
        if ($request->has('f_only_orders') && $request->f_only_orders == "true") {
            $order->where('type', 'order');
        }
        $order->orWhere('external_ref', 'ILIKE', "%$request->q%");

        $order->orWhereHas(
            'transport_order',
            function ($query) use ($request) {
                $query->whereHas(
                    'charter',
                    function ($query) use ($request) {
                        $query->where('name', 'ILIKE', "%$request->q%");
                    }
                );
                $query->orWhereHas(
                    'waypoint.address',
                    function ($query) use ($request) {
                        $query->where('zipcode', 'ILIKE', "%$request->q%");
                    }
                );
           
            }
        );
        return $order
            ->with([
                'contact',
                'contact.company',
            ])

            ->paginate(($request->size) ? Intval($request->size) : Config::get('user_settings.pagination'));
    }

Any help is welcome ! Thank you very much !