In the top right of the screen, you'll find the search bar - it's there on every page of the system. From here, you can search for goals or people. Search results will cover the entire organization, not just your own goals. When you find a result you're interested in, simply click on it to be take either to the Goal Hub (for goals) or the My Team page (for people).
The search engine will give results in real-time as you type - just keep typing a few more characters if you don't see the result you're looking for, or if you're seeing too many results to list.