RTL2832 USB for two frequencies

Hello , with gnuradio , I was able to generate (following the tutorials
on the net ) Narrow FM receiver that works with a USB RTL2832 . Now I’m
trying to figure out if I can manage to simultaneously monitor two
frequencies . Some of you can tell me if it is possible to achieve this
with a single key , perhaps by scanning continues between the two
frequencies that would be set manually.