从DataTable中的每个数组元素的另一个表中获取数据

I am working on a Laravel DataTable. I have an array of the field customer. I want to fetch the data from the other table using a foreach loop. How can I fetch data from another table in my for each element of the array?

$quotations = $this->quotationRepository->getAll()
    ->where([
        ['status', '!=', 'Draft Quotation']
    ])
    ->where('deleted', '=', '0')
    ->with('user', 'customer')
    ->get()
    ->map(function ($quotation) use ($dateFormat) {
        return [
            'id' => $quotation->id,
            'quotations_number' => $quotation->quotations_number,
            //'customer' => $cl,
            'customer' => unserialize($quotation->customer_id),
            'final_price' => $quotation->final_price,
            'date' => date($dateFormat, strtotime($quotation->date)),
            'exp_date' => date($dateFormat, strtotime($quotation->exp_date)),
            'payment_term' => $quotation->payment_term,
            'status' => $quotation->status
        ];
    });