You shouldn't be able to see them unless you worked for an agency that gave you access to those records, sealed or not. Per my understanding of juvenile law, what the TJJD (Texas Juvenile Justice Department) code means is that those "sealed" records can now be "opened" for judicial purposes in regards to the person that committed a crime in an adult court, or for background checks.
For example if I was arrested at age 14 for drug possession and completed my probation or residential lockup time, and then had my record sealed, when I'm pulled over at age 24 and they run my name they aren't going to see that I was arrested at age 14 for drugs. However, if those records are now "opened" because I committed a felony later on, or I never had my records sealed, they may pull up when my info is run.
I could be wrong, the internet seems to have everything, but it is my understanding that a juvenile's criminal history can not be made public unless they are tried as an adult, or make that history public themselves.