Modules

Select and autocomplete widget.

Provides configurable search pages at /search/user and /search/node.

Make sure your permissions are set correctly to avoid leaking information.

Hide non essential content form fields like publishing options and author.

Configure Form API states in form display settings.

Hide vertical tab items per role.

Drupal's main search module.

Use facets with core views.

Multiple facets in a single block.

Captcha from Cloudflare.

Enforce unique field values.