In reply to MariaJGlez:
As others have said, the attributes for sport and trad draws are a bit different, so any set you get for both tasks will be sub-optimal. Just to break this down as I see it:
Sport:
You want something comfortable to grab hold of and pull, generally they are short, weight is usually less important than durability because you will be ragging them against bolts a lot but only carrying a limited amount of weight on your harness. Normally they are relatively rigid for various reasons, including allowing them to remain hanging properly when you pull the rope down and leave them on the route for the next try. There are a number of companies that make cheap sets of sport draws.
Trad:
You want something lightweight because a full trad rack is quite a mass to have on your harness, you take either a range of QD lengths or extendable quickdraws (2 carabiners with a tripled over sling between them) because your gear placements will probably not be in a straight line. The draw not being rigid is desirable as it means it is less likely to push/pull a nut or hex out of its placement. Trad draws tend to be more expensive, particularly when you want to go light or buy separate slings to make extendable ones.
So overall it's worth thinking about what attributes are most important to you when you are climbing and whether you climb trad more often or sport more often.