The search.php file in the Nexmoe theme powers the sidebar search, but if pretty permalinks are disabled and you simply reference search in the theme settings, the search box will throw a “No input file specified.” error.
This happens because, with pretty permalinks off, every URL contains /index.php, while the original search.php was never written for that scenario. Open search.php and locate this snippet:
<div class="nexmoe-widget-wrap">
<div class="nexmoe-widget nexmoe-search">
<form class="search" method="post" action="./search" role="search" style="margin-bottom: 0px;">
<input type="search" placeholder="搜索" name="s" class="search-input">
</form>
</div>
</div>
Then change:
<form class="search" method="post" action="./search" role="search" style="margin-bottom: 0px;">
to:
<form class="search" method="post" action="./index.php/search" role="search" style="margin-bottom: 0px;">
After that, the search function will work.