When i export gridview data ,local unicode fonts are not supported

Thanks in advance,

It works fine for English language characters but it does not support local characters like “नमस्ते नेपाल”.
Please suggest me solutions for it.

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Put details that one can be able to understand. Things like what you have done, relevant code, et al

Here is the code.

use kartik\export\ExportMenu;
    echo  ExportMenu::widget([
                  'dataProvider' => $dataProvider,
                    'filterModel' => $searchModel,
                    'columns' => $gridColumns,