[SOLVED]How to ask for a topic merge?

Sometimes, users make different topics regarding the same hardware and issue, like these two posts:
http://forums.debian.net/viewtopic.php?f=7&t=135669
http://forums.debian.net/viewtopic.php?f=6&t=135662
And it's ok and normal (even that we all expect users know how to search, sometimes they don't even bother to, but sometimes they simply don't know, how to or that this feature exists).
So, at the event like that the same issue have two posts, how to ask for "merging topics"?
Dell Latitude E6410 - matrix is blinking
http://forums.debian.net/viewtopic.php?f=7&t=135669
Debian 9 stretch & MATE desktop - flickering screen
http://forums.debian.net/viewtopic.php?f=6&t=135662
And it's ok and normal (even that we all expect users know how to search, sometimes they don't even bother to, but sometimes they simply don't know, how to or that this feature exists).
So, at the event like that the same issue have two posts, how to ask for "merging topics"?