ESL here. To me, there is a very clear distinction between these terms, which also applies in my native language: A thiefs tries to steal without you noticing,

ESL here. To me, there is a very clear distinction between these terms, which also applies in my native language: A thiefs tries to steal without you noticing, a burglar is a thief that additionally enters a building, and a robber in contrast steals while intentionally confronting you. The intention and the level of danger each of these pose is quite different.