The coach praised his players' performances in their 1-0 victory over Poland to qualify from Group A, adding that the loss to Russia in their first game spurred them on to success
The Narodak beat Poland 1-0 in Wroclaw courtesy of a Petr Jiracek goal to send the co-hosts packing and ensure their own progression as Group A winners with second-placed Greece.
Bilek observed after the match that the 4-1 loss to Russia in his side's opening game was a turning point, with the squad learning from their mistakes in that game.
"We learned from our mistakes [against Russia] and were responsible in the following games, showing our qualities," the coach told reporters.
"We are very satisfied that we have beaten one of the hosts - especially after the two good games that they played [previously]. We improved a lot in the second half, we showed motivation and spirit.
"To be honest, we improved at the end of the first half, dominating possession, then, after Greece scored, I told my team to remain focused. We were patient and it paid off."
The 47-year-old went on to praise Tomas Hubschman, whose introduction to the starting XI after the thrashing by Russia coincided with Czech Republic winning all of their remaining group games.
"Hubschman improved us, but the whole team improved as well," he argued. "We had five midfielders and when all of them started to play more responsibly, we were a better side.
"Of course we were missing [Tomas] Rosicky, but we managed to win without him. Damian Kolar played a great game too.
"Now I'm only thinking about what will happen in the quarter-finals, I said before that this was our aim and that I wanted to play Germany, but now I may have to take it back!"