dba in Dallas

I need to apply for a DBA in Dallas county, TX, to coincide with my LLC.
The problem is there is a similar name listed as a dba. Can I still use it?
My business name will rarely if ever be seen by the public, since the dba is
a franchise.

Example:

My LLC is something like Mr. Vacuum, LLC
The dba I want is: Mr. Vacuum, LLC, dba Vacuums-R-Us (whereby Vacuums r-US
is the name of the franchise).
The dba currently registered is: Mr. Vacuum Sales and Service
Can I still use Mr. Vacuum, LLC, dba Vacuums-R-Us?

Yes. The d/b/a registration is simply that, a registration.

As long as your name is not an EXACT match, you shouldn't have any registration problems. A d/b/a registration does not protect you against claims of copyright or trademark.