I don't know how to set up two Acquia searches on your site. But I wonder if you tried Views with exposed filters? Or I wonder if you considered creating custom blocks with the Solr search?

You might be able to give your customers a unified search experience; and gently expose filters and refinements through blocks. For example a search on Amazon for a digital video camera gives me a block to filter:

Brand
* Any Brand
* Sony (15)
* Canon (33)
* MRR Wares (2)
etc

In this example a customer searches for a particular product. You can refine the search in two ways:
1) In the results you offer a custom block to filter the search, for example by brand.
2) Then when they are viewing a node, you can offer multiple blocks to recommend items which are similar by various taxonomy, such as brand, price range.

Enabled Filters block

Under Administer → Site configuration → Acquia Search click 'Enabled Filters'
You can select a filter such as Apache Solr Search: Filter by taxonomy Brand (as an example of a categorization vocabulary you may have)

Then, go to the Blocks configuration page and control where these filters show up (sidebar for example). This will show up on the search results page.

Recommendation block

With Acquia Search you can also create blocks for "Apache Solr recommendations"

Administer → Site configuration → Acquia Search
Scroll down to above Advanced configuration and click "Add a new content recommendation block"

You can make a 'recommendations' block based on a taxonomy term. This will analyse a current node a build a recommendations block based on a particular product type. You can then configure where this block should show up, for example based on a URL path.

After you make save the block it takes you to a block configuration page, where you can configure where to show the block.