As you self describe as Novice - - I urge you to develop your query using the standard query design view. Once it returns the correct set of records - then change it so SQL View and you can see the SQL text.
As to this note: Also, is it possible through a window/popup for the user to enter the search values instead of hard coding it with the Database.Symbol values? - - yes, one can call in a query's criteria from a text field in a Form. OR there is a feature called a Parameter Prompt - which can be put in the query design itself.