e1tekoap42

this highlighter has the following features:
<ul>
<li>works in frontend by using javascript ,so it has almost no pressure on the server side</li>
<li>support cache plugin</li>
<li>support UTF-8,GBK and GB2312 encoding search engine (eg:google.com,baidu.com)</li>
</ul>

Search engine keywords highlighter

highlight the keywords if visitor is from search engine

Arefly

想看看自己的文章被百度收录了没有？
快来使用这个插件吧！
这个插件可以让你检查你的文章是否在百度搜索结果内，同时会把结果直接显示在文章内容部分内
English: Check your post whether it is in Baidu Search Result.
<h4>Translators</h4>
<ul>
<li>Chinese, Simplified (zh_CN) – <a href="http://www.arefly.com/" rel="nofollow ugc">Arefly</a></li>
<li>Chinese, Traditional (zh_TW) – <a href="http://www.arefly.com" rel="nofollow ugc">Arefly</a></li>
<li>English (en_US) – <a href="http://www.arefly.com" rel="nofollow ugc">Arefly</a></li>
</ul>
If you have created your own language pack, or have an update of an existing one, you can send <a href="https://codex.wordpress.org/Translating_WordPress" rel="nofollow ugc">gettext PO and MO files</a> to <a href="http://www.arefly.com/about/" rel="nofollow ugc">Arefly</a> so that I can bundle it into Check Baidu Result. You can download the latest <a href="https://plugins.svn.wordpress.org/check-baidu-result/trunk/lang/check-baidu-result.pot" rel="nofollow ugc">POT file</a>.

Check Baidu Result

检查你的文章是否在百度搜索结果内

Search engine keywords highlighter vs Check Baidu Result