  We analysed spectroscopic data obtained with VLT-VIMOS for two
multiple-cluster systems, PLCKG$214.6+36.9$ and PLCKG$334.8-38.0$, discovered
via their thermal Sunyaev-Zel'dovich signal by $Planck$. Combining the Optical
spectroscopy, for the redshift determination, and photometric data from galaxy
surveys (SDSS, WISE, DESI), we were able to study the structure of the two
multiple-cluster systems, to determine their nature and the properties of their
member galaxies. We found that the two systems are populated mainly with
passive galaxies and that PLCKG$214.6+36.9$ consists of a pair of clusters at
redshift $z = 0.445$ and a background isolated cluster at $z = 0.498$, whereas
the system PLCKG$334.8-38.0$ is a chance association of three independent
clusters at redshifts $z = 0.367$, $z =0.292$, and $z = 0.33$. We also find
evidence for remaining star formation activity in the highest-redshift cluster
of PLCKG$214.6+36.9$, at $z = 0.498$.
