You can search materials by Title, Creator, Year, All Fields & Tags, or Everything by typing in your search terms in the bar at the top of your Zotero desktop. Use the dropdown menu to specify where you would like to search. This method will also search the full text of website snapshots.
In addition, Zotero has many options you can use to sort the materials in your LIbrary. Sorting will allow you to search materials using the following categories: Creator, Item Type, Date, Year, Publisher, Publication, Date Added, Date Modified, Extra, Attachments, Notes, etc.