Vukasin, if the client is interested in your proposal, you will receive a message or offer from the client, but if you never hear from the client or you receive a notification that your proposal was declined, then your proposal was rejected.
"No good deed goes unpunished." -- Clare Boothe Luce
When you apply for a position, the client is notified of your proposal. If the client is interested, they can send you a message to discuss further. Clients don't necessarily reply to each freelancer who applies to their job. You can also see on a job posting if anyone has been hired for the opening.