1. A computer-implemented method of searching for semantically equivalent questions using hybrid representations in a computer-implemented community of question and answer system, the method performed by one or more hardware processors, comprising: receiving a first question in natural language via a user interface; parsing the first question into tokens using a natural language processing technique; generating in-memory weighted bag of words representation of the first question based on the tokens, wherein weights associated with the bag of words are determined by training a neural network to learn the weights; generating in-memory convolutional neural networks based distributed vector representation of the first question based on the tokens, wherein parameters of the convolutional neural networks based distributed vector representation are determined by training the neural network to learn the parameters; retrieving a second question from a pool of questions stored in a storage device, wherein the second question represented in different representations comprising in-memory weighted bag of words representation and in-memory convolutional neural networks based distributed vector representation; and determining semantic similarity between the first question and the second question as a function of a first similarity computed based on the in-memory weighted bag of words representations of the first question and the second question, and a second similarity computed based on the in-memory convolutional neural networks based distributed vector representations of the first question and the second question, wherein parameters attributed to the first similarity and the second similarity in the function are learned by the neural network, wherein hardware memory representation of the neural network is transformed as the parameters are learned and updated, the first question represented in different representations comprising the in-memory weighted bag of words representation and the in-memory convolutional neural networks based distributed vector representation.