copying a directory structure with a particular file in directories below

Hello,
I need some help/advise on how to copy a directory structure with a
particular file in directories below the start directory.

Let's say I have many text files [*.txt] with many data files and other
files [*.data, *.*]
The directory I want to copy across to another area with only the text
files but which also retains the directory structure.

i.e.,

[root_directory]
|__[data]
|__[directory_1]
|__[direcotry_2]
| |__[directory_2.1]
|
|__[directory_3]
|
|__[directory_N]


I want to copy the directory [data] to another area with just the *.txt
files but retain the directory structure.

I tried to do this

cp -r `find /[root_directory]/[data] -name "*.txt"` .

NOTE: The above when I include the square brackets is meant to
represent the full name of the
directory and is not to be confused with anything else.

I could have wrote:

cp -r `find /root_directory/data/ -name "*.txt"` .

When doing this, all I get is the *.txt files without the directory
structure. If the *.txt files have the same name it will cause
problems. So I can copy the directory structure it would be great.

I hope you can understand the issue/problem statement from my
explanation.
If you have any questions please ask me.

Thanks,
ROuNIN

.