你可以使用:

Model::where('table_column', 'value')->orWhere('table_column', 'value')->get()

使用逻辑分组(Laravel 7.x/4.2)。在你的例子中，它是这样的:

Model::where(function ($query) {
    $query->where('a', '=', 1)
          ->orWhere('b', '=', 1);
})->where(function ($query) {
    $query->where('c', '=', 1)
          ->orWhere('d', '=', 1);
});

如果你想在Laravel 4中使用a,b,c,d的参数

Model::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);
});

如果你循环OR条件，你不需要第二个$查询->where来自其他帖子(实际上我不认为你一般需要，你可以在嵌套的where中使用orWhere如果更容易)

$attributes = ['first'=>'a','second'=>'b'];

$query->where(function ($query) use ($attributes) 
{
    foreach ($attributes as $key=>value)
    {
        //you can use orWhere the first time, doesn't need to be ->where
        $query->orWhere($key,$value);
    }
});

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';