# Searching and filtering

For public API endpoints that can return multiple resources, additional query parameters can be passed to constrain which resources are returned.

**Examples**

| Call | Effect |
|  --- | --- |
| **GET** `/users?last_name=Smith` | Searches for all users that have Smith as/in their `last_name` field. |
| **GET** `/instruments?isin=IE00BLRPQH31` | Searches for instruments with the specified ISIN. |