You can search for a profile by name by going to Search from the main menu and entering his name (or part of his name) in the Search by Username box, to left, and clicking Go.
All other searches can be for profiles, pics of videos.
You can search for members in any location. By default the location is set to your current location (I'm in London) and any distance (so, everyone/the whole world). To search for members in a specific location, click set a location and follow the instructions for setting a location
Once you have set a location, it will appear on the page above the 'set net location' link. You can set a distance from that location here too. If you live on a country border that is not easy to cross, you can restrict the results to the same country by selecting 'this country only'.
There are a whole host of other criteria on this page which you can set. You can tick as many or as few as you like but remember, each additional selection will reduce the number of results.
Any search can be saved. Regular members can have 1 saved search, and supporters can save 10 searches.
To save a search, enter a name for it in 'save this search'. That name will appear in future under 'my saved searches' which can be used not only on this page, but also to refine any of the built in searches available in the main menu ('search with', at the top of those pages). So for instance, if you save a search where you have selected an age range of 35-50, you can refine all the main menu built in searches like nearby, online etc. to your preferred age range.