In order to query serialized JSON data from MySQL’s JSON column using Laravel Eloquent, first we need to define cast property for the serialized JSON attribute in a model as below:

class Product extends Model
{

    protected $casts = [
        'meta' => 'json'
    ];
...
...
}

Then, use the following search query in the controller.

$keyword = strtolower($request->get('keyword'));
$product = Product::whereRaw('LOWER(meta->"$.test_field") LIKE ?', '%'.$keyword.'%');