The filter field allows you to quickly type in the partial name of an item in that directory and crush will filter down the file listing to only show items matching what you have typed.  It will also search keywords if they have been associated with a file.  You can always right click and add keywords on to a file.

[attachments|filter2.png]

I typed in 'blue' to only see that one item.

[attachments|filter1.png]