Dynamic bookmark with between filter or greater than AND less than

[patchrick843]

I need to create a dynamic bookmark filter on my app. Currently what I have is 

=MonthYear<MonthName(addmonths(today(),-1))

What I need is something like this 

=MonthYear<MonthName(addmonths(today(),-1)) & =MonthYear>MonthName(addmonths(today(),-12))

 I know this is not the correct syntax but how can I achieve this? 

[marcus_sommer]

The following worked for me directly with a hard-coded values but should be also possible with your expression:

=(Related>=100)*(Related<=110)

- Marcus