So, I opened the Library List screen wiki page and was surprised to find that it does not have a section about the magnifying glass on that screen. I'll fix that.
In the meantime, if you go to the bottom of the main page of the wiki and tap on FAQ, you'll see the following language:
Can I search using wildcards?
Yes, wildcards can be used for partial word searching. By using the asterisk symbol ( * ), you can generate a wildcard search and find specific words throughout a record.
Here are some examples:
String Result: Memento is the best database application on android
Search: Memento* (finds any field beginning with 'Memento')
Search: *database* (finds 'database' throughout the field)
Search: *best* *application* (finds fields containing both 'best' and 'application' within the field)
Can I search libraries using barcodes?
Yes, before you can scan barcodes, you must first:
Install “Barcode Scanner” by ZXing Team (also available to download through Memento interface).
Set up a field with the Barcode field type
When the above criteria have been filled, open the context menu > Barcode search';' then scan the barcode.
Maybe that will help.