Hobbsee's right, that would give you only Ubuntu bugs.
However, I get the feeling that what you mean is something like this:
1. Go to bugs.launchpad.net/~kitterman
2. Select "Search for bugs in distro / package / project"
3. Enter "Ubuntu" and hit search.
4. Get Ubuntu bugs related to you back.
Hobbsee's right, that would give you only Ubuntu bugs.
However, I get the feeling that what you mean is something like this:
1. Go to bugs.launchpad. net/~kitterman
2. Select "Search for bugs in distro / package / project"
3. Enter "Ubuntu" and hit search.
4. Get Ubuntu bugs related to you back.
Right?