Here's a tip - open your daw, then open a synth. Then make your own sounds, and get exact control over exactly everything, including stuff like this.
Ok, then, actual advice. There are plugins that do this; If you have logic, you can use Logic's Sub Bass plugin, which does this really really well (when I have this problem using my own resampled stuff I use that). Also check out waves RBass to add harmonics to the lows to make them more pronounced, I use this on all sub bass in all my songs.
You could also
I need to stop changing my sig
Hey, finally got soundcloud
https://soundcloud.com/h-e-l-l-o
some guy from facebook wrote:
-instead being would have said stop acting judgemental of others then yet on you mind is not yet acting judgemental