You can also use a freeze spray, also available at auto parts stores.
If you're cheap, like me & hate paying sooo much money for a can of liquid coolant, you could use a can of canned air, the kind for dusting out computers, turn it upside down & blast away. It's about -350F!!
It's the same thing as the automotive stuff, but colder by about 300deg and they put a bittering agent in it now to keep people from huffing it to get high. Like that'll stop 'em. HA!
So wear a chemical respirator/disposable mask, or put up with the bitter taste for about a day. IT'S HORRID!! Nothing I have found removes it from your mouth.
Now if you're a real freaking genius, or ultra nerd.
You can place a sopping wet rag, soaked in a kOH/NaOH solution over the bolts and setup an electolysis system to clean the rust enough to free the bolts. If your bolts aren't too big, and you do one at a time, you might get away with just using a big cell 9v/12v battery, or a small ATV/Motorcycle battery.
HEHE! Works like a champ.
Remember, anode corodes(collects), cathode releases (cleans). So make your bolt the negative, cathode.
I almost drove our entire Ford Exploder into a vat of Lye & Rods /w a big honking Power Supply!! *Tim The Tool Man Taylor Roo Rooo Roooo!!!*
But decided to just clean each part as needed.