Which are the fields you can search in using Advanced Search option?

In the Advanced search window, you can choose the fields to bring it under search operations purview. 
Just enable/disable the check boxes of the fields under Search In:
Title- Name of the Asset.
Description- Description given to the asset while uploading.
Author –email id of the user who ingested the asset is the default value, but this field can be edited.
Ingested By – Name of the user who ingested the asset.
Asset tags – Tags are keywords given to assets by a user. There are public tags as well as private tags.
Comments – Comments given to asset by different users.
Closed Caption- Text version of the spoken part of a video file.
Embedded metadata - Metadata stored and maintained within the asset. It cannot be edited.
Custom metadata- Metadata defined by users for an asset. It can be edited.
Asset id – Each Asset ingested into eMAM system is numbered stating from 1. 
UUID- A unique ID associated with asset. It is an alpha numeric string. If an asset has three versions, the UUID for each version will be different.
Markers: Markers of the assets.