The modal verb potere1 and the verb riuscire2 (as well as sapere) might translate to can in English, but they are not synonyms in Italian and have special usages.

Riuscire a + infinito means can or be able to in the sense of to manage. Some grammar texts often describe riuscire as being used when the ability to do/not do something is dependent upon ourselves or some physical limitation. In other words, whether we can or cannot do something is due to some factor or condition of ourselves (not on some outside force/factor):