searching in belongsToMany relationship in laravel 5 - php

Question

Actually i want to search those question which user want to search after select any subject or course.
if a remove either whereHas from subject or course its works but with both its not working.
Please give a better solution for searching in belongsToMany realtionship.
i have a question table with Question model class
class Question extends Model{
public function courses(){
return $this->belongsToMany('App\Models\Course','course_questions');
}
public function subjects(){
return $this->belongsToMany('App\Models\Subject','subject_questions');
}
}
and in my searchController
public function index(Request $request){
$questions = Question::with(['user','courses','branches','subjects','years','universities','question_type'])
->where("status","=",1)
->where(function($query) use($request){
$q = $request->q;
if(isset($q) && !is_null($q)){
$query->where("question","LIKE","%$q%");
}
})
->whereHas('subjects',function($query) use($request){
$subjects = $request->subject;
if(isset($subjects)){
$_subjects = explode(" ",$subjects);
$query->whereIn("slug",$_subjects)
->orWhereIn("subject_name",$_subjects);
}
})
->whereHas('courses',function($query) use($request){
$course = $request->course;
if(isset($course)){
$_course = explode(" ",$course);
$query->whereIn("slug",$_course)
->orWhereIn("course",$_course);
}
})
->paginate();
if($request->ajax()){
$returnHTML = view('questions.question_list')->with('questions', $questions)->render();
return response()->json(array('success' => true, 'pageContent'=>$returnHTML));
}

Answer 1

You should build your query probably this way - you should verify conditions before adding any constraints to your query:
$query = Question::with(['user','courses','branches','subjects','years','universities','question_type'])
->where("status","=",1);
$q = $request->q;
if(isset($q) && !is_null($q)) {
$query = $query->where("question","LIKE","%$q%");
}
$subjects = $request->subject;
if (isset($subjects)) {
$query = $query->whereHas('subjects',function($query) use($subjects){
$_subjects = explode(" ",$subjects);
$query->whereIn("slug",$_subjects)
->orWhereIn("subject_name",$_subjects);
});
}
$course = $request->course;
if (isset($course)) {
$query = $query->whereHas('courses',function($query) use($course ){
$_course = explode(" ",$course);
$query->whereIn("slug",$_course)
->orWhereIn("course",$_course);
});
}
$questions = $query->paginate();

Answer 2

$products = Product::query()->
WhereHas('categories', function ($q) use ($keyword) {
$q->where('products.name', $keyword)
->orWhere('categories.name', $keyword);
})->get();
This is how I have used in my project