Emtree is a buildable search tool that allows you to create search strings based on hierarchical facets and terms. It is helpful when researching multiple points of interest, using a term or facet to begin.
When beginning with a term, type it into the search box without quotes and select from the drop down that appears. Your search will extend below where specific terms may be selected:
From there you will see options to select a narrower term or continue throughout the tree for more terms:
Once you have selected the term you are wanting, you can take the query to the Search function specific to it. In this example you could take this query to "Disease Search" but if you were searching a medicine it would read "Drug Search". If you are wanting to add more to your search request, you can select "Add to Query Builder" where it will display at the top:
From there you can perform another search and add to your query string until ready to view the results.
Using the "Browse by Facet" option will bring up options that can expand into more narrow topics to hone in on the query term of your choice. It will also display how many results will be in that search from that term:
The Emtree function will also show information regarding history and synonyms of terms:
Once your query is complete, depending on which search function will be most appropriate between "Advanced", "Drug", or "Disease" you can further narrow your results with the limiters listed here: