How can I filter by taxonomy term after the first level filter?

I have two content types (Book and Video), each with its own vocabularies: Book Vocabulary with Newspaper, Novel, and Magazine; Video Vocabulary with Movie, TV Show, and Documentary.

I have a view showing all the Book and Video nodes. My goal is to be able to filter by content type first, then by taxonomy terms (of the selected vocabulary/content type).

I’m not positive this will work correctly but you could try utilizing field groups.

1. enter your view, under filter criteria select add. Now under category drop-down select content. Find the option “Content Type” and select it, then select “Add and configure filter criteria”. Select top checkbox “expose this filter to visitors” then select content type “book” and also content type “video” then select apply.
2. Again select add, go to content, and this time select “has taxonomy terms”, again expose filter, and select the specific terms you mentioned above, then apply. You will need to do this step twice, so you have a taxonomy filter for both book taxonomies and video taxonomies.
3. Now select the arrow just to the right of “add”, then select “and/or rearrange”. In the top right select “create new filter group”. You will want to select all operators as “or”. Arrange group one to have “content: content type = book” as well as “content: has taxonomy terms” and arrange group two to have “content: content type = video” as well as “content: has taxonomy terms”.

Select apply and then save the view and see if that does the trick