Google has just announced today that they have now included the ability for users to search for "regular expressions" inside Docs on the web. An example of this can be found below in the image, which showcases what is being typed in the box that a user is trying to find. From now on, when a user goes to try and find something in Docs, (the example used below is a search for documents and files that contain all US zip codes) below the "find" and "replace with" search fields there will now be a box to check that allows users to Match up documents that are using regular expressions.
While this isn't generally the way that most users will probably try and search for documents, as regular expressions are a common method for filtering text within programming, the ability to search for text in this manner will certainly help out anyone who has programming knowledge and may use regular expressions to search for things in other programs or apps. While regular expressions can now be used to search for text in Docs on the web, it's likely that not all regular expressions are supported with this new change as Google notes that users can navigate to the Help Center to find out more about which expressions are supported within the service.
While this is only included in the web version for now, those who use Docs on the web can expect regular expressions to be included within the next few days, as it's listed that the rollout pace is set for anywhere from one to three days, which means some users will see the capability to search for text using regular expressions today while others may not see it till the end of the work week. Google doesn't mention a time frame for when they'll add this option for searching to the Docs app on Android, but Google updates their apps pretty frequently and the most recent update to Docs on Android was somewhere around the middle of August, so there is a chance that the next update for the Android app could include this new capability.