How you find information. It looks like good for 2-3 days or week but after a month you could not able to find the information.
Then I've got a script (https://github.com/karlicoss/telegram2org) that checks for new messages in this group every hour or so (cron) and appends Org-mode formatted messages to a special file. There are some extra features, like automatically mapping select senders into org-mode tags (yes, I do keep tags for closest friends :D ).
That makes it always show up when I search something (adressing the problem of finding information), I also can easily transform it into a proper todo/task if necessary.