I would like to add multiple classifications into one search (see screenshot). But it seems like if I add one, then click on "select classification" it just erases the previous selection.

For example, I'd like to make multiple selections for an ongoing project. (Sort of like I can make multiple selections for Readership Level.)

For this project, I need to keep up with new books in many related LC subjects:
T174
TL581
TL790
TL794 (for the TLs, a range would be okay)
HD9711
QB500
KNQ3469

Is this possible? If so, how do I do that? I know I can create many different search lists, one with each of the above subjects, but I want to combine the subjects into one search I can run monthly. I have many different subject listings so don't want to have to run them separately.