First off, Welcome to MPGH. To find working hacks simply go to the Combat arms main. Combat Arms Hacks - MPGH - MultiPlayer Game Hacking and look for a thread that was posted recently so it isn't patched or detected.
For Example, This thread was made 11 hours ago so you can bet the hack is up to date and won't be detected. http://www.mpgh.net/forum/164-combat...kill-more.html You'll want to click the download button.
So now you have the hack, but how do you use it?
You need an injector.
You can find all the injectors here http://www.mpgh.net/forum/292-combat...s-multi-tools/
I would recommend you use PerX (the download for it is found at the bottom of this post) http://www.mpgh.net/forum/292-combat...s-updated.html
There is a video at the top of the post telling you how to use PerX
But all you have to do is extract the hack rar file using winrar or a similar program. Then in PerX you'll want to locate the hack and then set the process name to engine.exe Set the options to auto inject and close on injection. Start Combat arms.