Your upper body has multiple muscle groups. There is your chest, shoulders, back, and arms.
To increase strength in your upper body, you will need to lift weights and eat a high protein diet to increase muscle size and strength.
I would do a simple
1. legs
2. shoulders arms
3. back chest
split
I have a full sample workout routine you can follow in this thread here ->
http://www.evolutionary.org/forums/...uested-my-daily-training-blueprint-33382.html
The best exercises to increase strength are multi joint movements because they train multiple muscle groups at once. Things like the bench press, overhead barbell press, bent over row and wide grip chin up. You shouldn't neglect isolation movements like bicep curls but your primary focus should be the big compound lifts.