Bash – Search commands in history with discontinuous keywords

Bash Reference Manual says:

Readline provides commands for searching through the command history for lines containing a specified string

You want a regexp instead of fixed string.

Try hstr:
1. Installation
2. Configuration

You should see something like this with hstr:

Update:
Another tool is fzf.

1. Install: git clone --depth 1 https://github.com/junegunn/fzf.git ~/.fzf && ~/.fzf/install

2. Re-source your ~/.bashrc: source ~/.bashrc

You should see something like this with fzf:

The apropos command reads from a cache. It's possible that recently-installed man pages are not yet referenced in that cache. Generally the cache is updated either after each package installation or in a cron job, I don't know how it's set up on CentOS.

To update the cache, run mandb. There may be a prefered way to run it on your distribution (e.g. as a dedicated user), see if you have a system crontab entry (e.g. /etc/cron.daily/man-db or a line in /etc/crontab) and if you do, run that instead of calling mandb directly.