HMDB supports advanced searching using a powerful search engine based on the Lucene query language. HMDB text search supports boolean logic (AND, OR, NOT operations). To match a string exactly, place quotes around your search term (for example "acetic acid" will only match the acetic followed by acid, it will not match acetic or acid alone). You can also search using "wild cards" by inserting a "*" in your search term. For example, searching for "acet*" will match all words starting with "acet". In addition, text search supports parenthetical groupings, and prepended +plus and -minus operators.
|methylhistidine AND poultry||Find all entries containing both methylhistidine and poultry in the metabocard|
|(histidine OR poultry) AND NOT glycolylneuraminic||Find all metabolites containing histidine, poultry or both, but not containing glycolylneuraminic|
|"acetic acid"||Find all metabolites where the entire term "acetic acid" is found. In other words, don't match "acetic" or "acid" alone.|
|"acetic acid" AND biofluid_source:urine||Find all urinary metabolites where the entire term "acetic acid" is found.|
|name:acet* AND biofluid_source:urine||Find all urinary metabolites with a word in the name starting with "acet".|