# Searching and Browsing The UMLS code systems are displayed in the single view, where each code system is grouped under a top-level node that represents the code system itself. The code system concepts are organized in their respective hierarchies and are represented by their native ID, term, and their unique UMLS atomic ID. UMLS codes are not editable within Snow Owl. UMLS concepts can be searched via Snow Owl’s Advance Search feature or using the **Quick Search Widget** located in the main toolbar. UMLS codes can be assigned to Value Sets, Mapping Sets, or as target concepts in Map type SNOMED CT Reference Sets. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.b2ihealthcare.com/snow-owl-authoring-platform/umls-code-systems/searching-and-browsing.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.