Try with

$search = DB::table('scores')->where('score', '>', $number)->orderByRaw('RAND()')->first(); 

Look for numbers higher then 42, and sort it from low to high with a limit of 1.

I tried this solution, but I am getting a weird result. If ever my score is 3, the result will be 30. If the score is 2 the result will be 20 instead of 5 which is the nearest highest score.

Btw, my data is almost consist of 400 scores on my tables.

$secondsearch = DB::table('scores')->where('score', '>=', $score)->orderBy('score', 'ASC')->take(1)->first();

assuming you have the model built...

public function nextHighest($number) {
    return Score::orderBy('score', 'asc')->where('score', '>', $number)->firstOrFail();
}

I didn't test that code but I think it should do what you want. Let me know, thanks.