I am new to Laravel but started from Laravel 5.0.

I got 2 tables: Doctors

        class CreateDoctorsTable extends Migration {
        	public function up()
    	{
    		Schema::create('doctors', function(Blueprint $table)
    	   {
       	$table->increments('id');
                $table->string('url')->unique();
                $table->string('name');
                $table->text('brief');
                $table->text('text');
                $table->string('small-photo');
                $table->string('large-photo');
                $table->softDeletes();
                $table->timestamps();    		});	}
    	public function down()
    	{Schema::drop('doctors');  	}
    }

And Lesson:

    class CreateLessonsTable extends Migration {
    	public function up()
    	{
    		Schema::create('lessons', function(Blueprint $table)
    		{
    			$table->increments('id');
                $table->string('title');
                $table->text('body');
                $table->integer('doctor_id');
    			$table->timestamps();
    		});
    	}
    	public function down()
    	{
    		Schema::drop('lessons');
    	}
    }

When i use this:

    $doc = Doctor::find(1);
    $les =  Lesson::whereDoctorId($doc->id)->get();
    dd($les);

I got no problems and got 2 records of Lessons.

But if i use

    $doc = Doctor::find(1);
    dd($doc->lessons());

I got no records at all:

HasMany {#167 ▼ #foreignKey: "lessons.doctor_id" #localKey: "id" #query: Builder {#170 ▶} #parent: Doctor {#168 ▶} #related: Lesson {#160 ▼ #connection: null #table: null #primaryKey: "id" #perPage: 15 +incrementing: true +timestamps: true #attributes: [] #original: [] #relations: [] #hidden: [] #visible: [] #appends: [] #fillable: [] #guarded: array:1 [▶] #dates: [] #casts: [] #touches: [] #observables: [] #with: [] #morphClass: null +exists: false } }

My models are:

    class Doctor extends Eloquent {
      protected $fillable =   ['name', 'url', 'text'];

      public function lessons()
      {
          return $this->hasMany('App\Lesson');
      }
    }
    
     class Lesson extends Model {
        public function doctors()
        {
           return $this->belongsTo('App\Doctor');
        }

      } 

And for example i got this data:

In Doctors 2 rows with id = 1 and 2 In Lessons 3 rows: id =1 doctor_id = 1 id =2 doctor_id = 1 id =3 doctor_id = 2

I already mad, dont understand why i cant use ORM in a right way? Any help plz...