While developing a platform that compares product prices and characteristics across various Italian e-commerce websites, the need to retrieve similar products across the different and ever changing websites arose. In this thesis, we approach the challenge by setting up a task of retrieval of similar products given a starting product, where each product is defined solely by its textual attributes. Particular focus is put on the zero-shot scenario, where the model performance is evaluated on both products and websites that have not been seen during training. Our goal is to produce a model that can generalize well and be easily implemented in the real-world use case.