At the top of the various Acquisition pages there is a quick search box where you can perform either a Vendor Search or an Order Search.
In the Vendor Search you can enter any part of the vendor name to get results.
Using the Orders Search you can search for items that have been ordered with or without the vendor.
You can enter info in one or both fields and you can enter any part of the title and/or vendor name.
Clicking the plus sign to the right of the Vendor search box will expand the search and allow you to search for additional fields.
Clicking Advanced Search to the right of the search button will give you all of the order search options available.