You edited after I replied, but looking at your edit I guess my reply would remain the same.
The point is to have an input search form that is user friendly, not programmer friendly. the Lotus Approach database we are using currently has this. We do a ctrl+F which brings up a blank form that has the same fields as our main form including the subforms, then we type in criteria in ANY of the fields in that blank form and hit enter and it returns the results.
Filter by form does not do this. It will not filter on the subforms for one thing, so we have to actually go to another form to perform a search on what we see on the subform on the main page rather than doing it right from the front page. In Lotus whatever we type in is searched on without having to use wildcards. So it will return everything starting with or containing what we type in. I have also been unable to use the enter key to apply the filter. Yes I did make it so a keystroke combination will do it, but boss wants it to be just one key not two so ^A or another combination is unacceptable to her. Access will not let me use {Enter} or {Esc} as hotkeys.
I'm having trouble believing that it is not possible to create this same functionality in Access. It makes no sense to me whatsoever that Access, which is supposed to be so fantastically great, cannot do what Approach can do when Approach is supposed to not be as good. So far I've tried QBF, Filter by Form, and anything else everyone suggests and not one thing has worked like my boss wants it to. There has to be a solution out there. I have the database fully functional with this last exception. I can certainly create queries for all our most common searches, which is what I've had to resort to, but if at all possible the boss would like me to find a way to recreate that search function in Access.