Full structure retrieval means that a structural fragment entered into the search by the user is fully consistent with the retrieved hit fragment. To accelerate this process, we had previously normalized the molecular structure of all molecules in the FADB-China. The molecular structure to be retrieved was normalized in real time and then matched to all normalized molecular structures in the FADB-China, and molecules matching the exact structure were retrieved. Fragment retrieval (substructure retrieval) means that the submitted structure is a fragment and is therefore a connected subgraph of the hit structure. The similarity retrieval function employs a Tanimoto coefficient-based similarity algorithm. The retrieved molecular structure was iteratively compared to the molecules stored in the database, and the search eventually returned the 20 most similar illegal additives. The MCS retrieval function was based on the fMCS algorithm. This retrieval method differs from similarity retrieval in that it focuses more on the complete matching of partial structural fragments rather than the similarity of the overall structure. A text retrieval method is also available for searches based on the synonyms, CAS number, InChI, InChI key, and IUPAC name.