You need to be able to quickly find a word in a text field. What should you do?
Create a single field index in descending order, and do a query for the word.
Create a text index on the field and do a $text Query.
Create a $regex on the fields, and do a $regex query. Argument: You need a text index in order to perform a $text query on a field. $text query uses the text index under the hood References: $text query Text index
Do a $text query.