Can I lie if someone asks me if I know a certain story and I lie with a "yes" because I know that is what he would like to hear?

No, it is absolutely not permissible. This is exactly the type of lie we must avoid. When someone asks you if you know a story, saying yes when you don't know it just to make them happy or to avoid seeming ignorant is a form of deception, and the Torah commands us to distance ourselves from lies. The Chazon Ish teaches us that out of all the topics discussed by our sages, lying is one area where they were extremely stringent. Why? Because the signature of Hashem is emet, truth. We cannot simply lie to please people or to make ourselves look good. If someone asks you if you know a story and you don't know it, the correct response is simple: say you don't know. There is no embarrassment in saying "I don't know" or "I haven't heard that story." In fact, this is the mark of an honest person and a true Torah scholar. The great tzaddikim would always minimize what they knew rather than pretend to know more. What you're describing falls into the category of lies we tell just to impress people or to avoid looking bad. These are exactly the types of lies that become habitual. We start lying about small things, and eventually it becomes our nature to lie about bigger things. If you live one day without lying, you'll see how difficult it is because we've become so accustomed to these "small" lies. Better to be honest and say you don't know the story. If they want to tell it to you, listen with interest. That's the proper derech, the proper way to conduct yourself.