enomoto celtislab

You are using a tag cloud of the standard, and you do not want to display tags that belong to the category not related to the article. 
Try this widget. 
Based on the category of the display article, this widget gets the tag from the article categories of related range. 
For the article there is no category of post page, etc., or by setting <code>all category</code>, <code>internal link article</code>, it displays the tag by examining the related category. 
If you check the ‘internal link article’, get a category from the internal links to articles.
Select Category related range
<ul>
<li>All Category (unrelated article)</li>
<li>Current article Category</li>
<li>Include child category tree</li>
<li>Include parent category tree</li>
<li>Include internal linked article Category</li>
<li>Exclude Category</li>
</ul>
Other parameters : Display format, Sort by, Order, Font size, Number of tags to display, …
<a href="http://celtislab.net/wp_plugin_DCTagCloud/" title="Documentation in Japanese" rel="nofollow ugc">日本語の説明</a>

DynamicCategoryTagCloud

Displays the tag cloud dynamically from related articles belonging to the category of the display article

Thomas Schmall

Tag clouds and Archives are useful for visitors, but also for search engines to find and index what topics your blog relates to. “Post Tags and Archives” makes it easy to add Tag Clouds or Archives to posts and pages via shortcodes. 
Before, you could only put it in the sidebar or widgets. That could hurt the search ranking for relevant terms and crowds the sidebar. So one either had to truncate the cloud and archive – or get rid of them (or use some more complicated trickery). 
Now you can just drop them in your posts and change the look easily via the options.
<h3>Options</h3>
Should be self-explanatory.
The advanced features: Please be careful with the HTML parts. 
The archive-format setting “options for dropdown-menu” is for people who want to setup forms. You have to add a proper form yourself – with select/post and all. Then this feature will add all archives (in the type you chose) as 
<h3>TODO</h3>
<ul>
<li>add products tag support 
Probably like this: 
$args = array( 
 ‘number’ => 15, 
 ‘taxonomy’ => ‘product_tag’ 
); 
return $args;Theoretically functional: from WP 1.5 (most features from: 2.5. “separator”-option from 2.9, “Tags-Order” for tags feature only from 3.5)</li>
</ul>

Post Tags and Archives

Display the Tag Cloud or the Archive directly in posts and pages, and change their look in the options.

DynamicCategoryTagCloud vs Post Tags and Archives