Hello, you need nstall tweak tool, please install to this way:
yum install gnome-tweak-tool
later open tweak-tool and the "window" tab you see the titlebar with the Maximize and Minimize buttons, just you need enable this, this happen cuz gnome disable this buttons, but with tweak tool you can solved this.
also you need remember this:
Maximize = Meta button + Up Minimize = Meta Button + H
good luck :)