Based on this:
$ yum list xampp
Loaded plugins: fastestmirror, langpacks, priorities
Loading mirror speeds from cached hostfile
* centos-sclo-rh: mirror.as29550.net
* centos-sclo-sclo: mirror.freethought-internet.co.uk
* elrepo: mirrors.coreix.net
* nux-dextop: mirror.li.nux.ro
Error: No matching Packages to list
$ yum group list xampp
Loaded plugins: fastestmirror, langpacks, priorities
Loading mirror speeds from cached hostfile
* centos-sclo-rh: repo.uk.bigstepcloud.com
* centos-sclo-sclo: repo.uk.bigstepcloud.com
* elrepo: mirrors.coreix.net
* nux-dextop: mirror.li.nux.ro
Warning: no environments/groups match: xampp
$ cat /etc/*release*
CentOS Linux release 7.7.1908 (Core)
...
and this:
$ yum search xampp
Loaded plugins: fastestmirror, langpacks, priorities
Loading mirror speeds from cached hostfile
* centos-sclo-rh: repo.uk.bigstepcloud.com
* centos-sclo-sclo: mozart.ee.ic.ac.uk
* elrepo: mirrors.coreix.net
* nux-dextop: mirror.li.nux.ro
Warning: No matches found for: xampp
No matches found