ModelName::where(function ($query) use ($a) {
    $query->where('a', '=', $a)->orWhereNull('a');

})
->where(function ($query) use ($b,$c) {
    $query->where('b', '=', $b)
          ->orWhere('c', '=', $c);
})->where('d',$d);

输出查询:

SELECT * FROM ModelName WHERE (a='a'或a为空)AND (b='b'或 c='c') AND d='d';

$a， $b， $c， $d可以是查询的动态值

 ->where(function($query) use ($a, $b)
        {
            $query->where('a', $a)
                  ->orWhere('b',$b);
        })
 ->where(function($query) use ($c, $d)
        {
            $query->where('c', $c)
                  ->orWhere('d',$d);
        })

YourModel::where(function ($query) use($a,$b) {
    $query->where('a','=',$a)
          ->orWhere('b','=', $b);
})->where(function ($query) use ($c,$d) {
    $query->where('c','=',$c)
          ->orWhere('d','=',$d);
});

ModelName::where(function ($query) use ($a) {
    $query->where('a', '=', $a)->orWhereNull('a');

})
->where(function ($query) use ($b,$c) {
    $query->where('b', '=', $b)
          ->orWhere('c', '=', $c);
})->where('d',$d);

输出查询:

SELECT * FROM ModelName WHERE (a='a'或a为空)AND (b='b'或 c='c') AND d='d';

这对我很有用

$business = Model::where('model_id', $model_id1)->orWhere('model_id', $model_id2)->first();

你也可以使用查询作用域来让事情变得更整洁，所以你可以这样做:

Invoice::where('account', 27)->notPaidAt($date)->get();

然后在你的模型中

public function scopeNotPaidAt($query, $asAt)
{
    $query = $query->where(function ($query) use ($asAt) { 
        $query->where('paid', '=', '0000-00-00')->orWhere('paid', '>=', $asAt); 
    });
    return $query;    
}