# esearch > Perform a new Entrez search using terms in indexed fields. > It is part of the `edirect` package. > More information: . - Search the pubmed database for selective serotonin reuptake inhibitor: `esearch -db pubmed -query "{{selective serotonin reuptake inhibitor}}"` - Search the nucleotide database for sequences whose metadata contain insulin and rodents: `esearch -db nuccore -query "{{insulin [PROT] AND rodents [ORGN]}}"`