I want to offer some good closing questions that I will often use near the end of a conversation. You can check them out here. These have worked for me... I hope they'll work for you as well.
Sometimes a conversation doesn't lead towards spiritual things, no matter how hard I try. A friend of mine has taught me to always ask at the end of such a conversation if I can pray for the person I'm sharing with (right then and there)... for healing, or just for a blessing, or, perhaps, for something they're dealing with or struggling with. In this prayer I always ask God to reveal Himself to them.
Also, in Europe, it's important to be aware of their apprehension. Many people won't be comfortable with you "laying hands on them" when you pray... and that's okay. Just do whatever they'll allow you to do.
I want to encourage you to continue to pray for opportunities, that you'll recognize them and make the most of them when it comes to lost people. It's a prayer Jesus told us to pray!
Then he said to his disciples, "The harvest is plentiful but the workers are few. Ask the Lord of the harvest, therefore, to send out workers into his harvest field." - Matthew 9:37-38