Even the best, most expensive woodworking tools will only cut as well as their bits or blades. If those saw blades or bits are covered with pitch (sap from wood that accumulates on the tool over time), they will likely heat up and become dull, in addition to losing their ability to hold an edge.
You can keep your cutting implements in top condition by cleaning them regularly with a pitch cleaning solution. You'll find a number of options at your local fine woodworking supplier.
However, there is another option that you may already have on hand. It is best to avoid using abrasive cleaners on your bits or blades, as they can scratch the surface of the tool which may affect performance. Additionally, scratches in the surface of the bit or blade will fill with pitch, making it more difficult to clean the next time.
A terrific alternative solution is to soak your bits or blades with oven cleaner. It is non-abrasive, yet designed to get out tough, baked-on stains, which is precisely what happens to sap when it accumulates on your tools and is heated by the friction of use.
You might also try soaking the blades or bits in kerosene or mineral spirits overnight, then scrub them with a non-abrasive kitchen cleaning pad. However, when employing this solution remember that the solvents are extremely flammable, so take appropriate precautions.