There are two types of knowledge. The first one is pure knowledge and the second one is applied knowledge. Applied knowledge may benefit you directly and immediately but pure knowledge benefits you indirectly in the long run.
If there are some things that you have studied or understood that you are unable to put into practice, do not get disheartened. Sometime in the future, if you do not discard the knowledge you have as impractical, it will be of use to you.
Often people discard the pure knowledge for its lack of immediate application. In fact these two types of knowledge compliment each other. Applied knowledge without pure knowledge remains weak. And pure knowledge without application will remain unfulfilled.
Do not discard or label the knowledge as impractical. Do not label yourself as weak or unworthy because you are unable to apply the knowledge in your day-to-day life.
Sometimes when you are alone in nature, silent, taking a walk, looking at the sand on the beach, a bird in the sky, or while meditating – suddenly the knowledge will emerge and you will recognize the knowledge dawning in your life.