모바일 검색 부분질문좀드리겠습니다?

<fieldset id="bo_sch">
    <legend>게시물 검색</legend>

    <form name="fsearch" method="get">
    <input type="hidden" name="bo_table" value="<?php echo $bo_table ?>">
    <input type="hidden" name="sca" value="<?php echo $sca ?>">
    <input type="hidden" name="sop" value="and">
    <label for="sfl" class="sound_only">검색대상</label>
   <!-- <select name="sfl" id="sfl">
        <option value="wr_subject"<?php echo get_selected($sfl, 'wr_subject', true); ?>>제목</option>
        <option value="wr_content"<?php echo get_selected($sfl, 'wr_content'); ?>>내용</option>
        <option value="wr_subject||wr_content"<?php echo get_selected($sfl, 'wr_subject||wr_content'); ?>>제목+내용</option>
        <option value="mb_id,1"<?php echo get_selected($sfl, 'mb_id,1'); ?>>회원아이디</option>
        <option value="mb_id,0"<?php echo get_selected($sfl, 'mb_id,0'); ?>>회원아이디(코)</option>
        <option value="wr_name,1"<?php echo get_selected($sfl, 'wr_name,1'); ?>>글쓴이</option>
        <option value="wr_name,0"<?php echo get_selected($sfl, 'wr_name,0'); ?>>글쓴이(코)</option>
    </select>-->
    <input name="stx" value="<?php echo stripslashes($stx) ?>" placeholder="제품명을 입력해주세요." required id="stx" class="sch_input" size="15" maxlength="20">
    <button type="submit" value="검색" class="sch_btn"><i class="fa fa-search" aria-hidden="true"></i> <span class="sound_only">검색</span></button>
    </form>
</fieldset>