South Korea's hopes of advancing to the second round were dealt a major blow on Sunday courtesy of a 4-2 reverse at the hands of Algeria.
That result left Hong Myung-bo's men bottom of Group H, with just one point from their two matches thus far.
With arguably the toughest test yet to come - against Belgium on Thursday - South Korea need to beat Marc Wilmots' team and hope Algeria fail to win against Russia to have any chance of making the last 16.
Son, 21, feels it is imperative a youthful South Korea side learn from their previous fixtures.
"We have a young team and most of the players are in their first World Cup," he said.
"It's true that I felt we needed (an on-field leader). But we can't always have such players. Ultimately, we have to overcome problems on our own.
"The loss is already in the past and it's important that we get ready for the next one.
"We made mistakes that we never should have. A game like that should never happen again and hopefully we all learned something from this."
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