What you are experiencing is correct.
We have same problem. There are many technical terms and we need to copy tags not to make a mistake in description
While there is not a way to specifically copy all the tags from one piece of content to another, the new Create a Copy feature of 2015.2 / Jive 9 would give you a similar effect. You could use the feature to create a copy of whatever document has the tags you need, and simply edit the content from there, or create a standing template that could be copied multiple times, depending on your specific use case. Tags are carried over when you use this feature. The copies can be created as a document, discussion, or blog post, so you're not limited to only documents. You can read a little more about how Create a Copy works in A Sneak Peek: Jive-n 2015.2.
I hope that helps!