Vacuum Full not clean the table

Dear All,

Along with saying hello, I would like to consult about a failure that is
happening to me with a PG 9.2 base and with a table that weighs 116GB and
its index 13Gb, mounted on a Linux Centos 7.2 with 4Core and 32Ram.
The failure occurs mainly in that I execute a Vacuum Full on the table and
it ends after 6 hours, but it does not clean anything. When checking the
dead tuples I realize that they follow the same dirty records in the table.
REF: (table of 420MM records with 20MM dead tuples)

I hope you can guide me in finding a solution to clean that table.

Greetings and many thanks to the Postgresql.org community
Atte.

*Erik Serrano*