The magnetic field around a wire carrying a current is not the same strength everywhere. Two things decide how strong it is.
The first is the current. A larger current produces a stronger magnetic field. If you increase the current, the field becomes stronger, and the compass needles near the wire respond more strongly.
The second is the distance from the wire. The field is strongest close to the wire and gets weaker as you move away. On a field diagram this shows as circles that are close together near the wire and spread further apart farther out.
So to make the field at a point stronger, you can increase the current or move closer to the wire.
