You can search by file name, contents or modified date
To search by file name only use name:myfile.txt
To search file contents only use contents:my term
You can substitute letters, words and phrases with an asterisk name:myfile*
To search for an exact phrase use quote marks "my exact phrase"
To search for files modified on a specific date use YYYY-MM-DD modified:2017-08-05
Dates can be whole months or years modified:2017-08 or modified:2017
You can search within date ranges using square brackets and the TO keyword modified:[2017-08 TO NOW]
You can combine search terms using the AND keyword name:myfile.txt AND modified:[2017-08 TO NOW]
For more advanced searches use the query builder