Cathe's off at a fitness conference, so I'll step in here, if you don't mind!
The bench press is a compound movement (working more than one joint and muscle group) that works the chest, but also the front shoulder and triceps. You can isolate the chest more by doing flyes, an isolation move that works one joint and one muscle group. You can give your chest more work by doing what is called "pre-exhausting," that is, doing an isolation move for the main muscle (flyes for the chest), then immediately doing a compound move for the same muscle group (bench presses). The chest will be a bit tired already (thus "pre-exhausted") and will feel the presses much more. This technique also works well if you find that your shoulders/triceps "give out" before your chest feels sufficiently worked.