Feature extraction from pure text
That is the real-world! in text analysis you usually end up with a extremely high-dimensional representation. First of all, I always recommend TF-IDF over original BoW (CountVectrizer).
To end up with a low-dimensional space, you may use this naive approach which is not written efficient in computational way but the approach gives you an idea where you need to go. It will be more clear when I add explanations to the notebook soon.