The barryvdh/laravel-dompdf set orientation to landscape not dispaly unicode correctly

Question

I have a project where I need to display Unicode characters. I've successfully displayed them in portrait paper orientation. However, when I switch to landscape orientation, the characters do not display correctly.

Here is my laravel project and packages :

• laravel: 10.0,
• php: 8.1.0,
• barryvdh/laravel-dompdf: 2.0.1,
• barryvdh/laravel-snappy": 1.0.2,

i want to display Unicode : ក្រុមហ៊ុន but it showing គោលបំណង

Here is a function that I use to generate PDFs :

public function LogReportRender($id)
{
    $batchSize = 14;
    $offset = 0;
    $all_requests = [];
    $request_data = [];
    $log_report = ReportLog::find($id);
    $title = $log_report->name;
   
    
    do {
        $requests = AppRequest::where('form_id', $log_report->parent_id)
                    ->where('is_active', true)
                    ->where('main_status_id', MainStatusId::Complete)
                    ->skip($offset)
                    ->take($batchSize)
                    ->orderBy('request_date','asc')
                    ->get()
                    ->toArray();
        $all_requests[] = $requests;
        $offset += $batchSize;
    } while (!empty($requests));
    if (empty(end($all_requests))) {
        array_pop($all_requests);
    }
    $flattenedItems = array_merge(...$all_requests);
    $allIds = array_column($flattenedItems, 'id');
    if(count($all_requests) > 0){
        $request_data = RequestData::whereIn('request_id',$allIds)
                        ->where('is_active',true)
                        ->get();
    }
    if(count($all_requests) < 0){
        return back()->withInput()->with('export_msg', 'Report can not preview, input not yet complete');
    }
    $form_name = strtolower(str_replace('-', '_', $log_report->code));
    $view_path = 'layout.report.form.'.$form_name.'_all';
    $param = [
        'all_requests' => $all_requests,
        'request_data' => $request_data,
        'report' => $log_report,
    ];
    $pdf = PDF::loadView($view_path,$param)
            ->setPaper('a4')
            ->setOrientation('landscape')
            ->setOption('margin-bottom', 0);
    return $pdf->stream($title);
}