In the "hard" case (Figure ) for all representations different most similar molecules were found. By visual comparison it can be seen that LatentGAN's latent vectors and ECFP descriptors provided the most similar structures, keeping the biggest part of scaffold. The search with VQGAE feature vectors was able to identify relatively close analogue, but, in case of VQGAE latent vectors the structure has different than the given query. A possible explanation is the limited use of codebook vectors mentioned in the fragment analysis section. Since some fragment vectors correspond to different fragments, collision effects similar to those seen with short fingerprints can be expected.