To save a search in Discover@MU, click the stacked dot menu on the right right of the search results.
Select Save Search from the dropdown. Your search will automatically appear in the Search Name and Query fields. You have the option to rename the search (as in this example) and add a description. Click Save at the bottom of the screen. This way you can come back and run the search again.
Your Saved Searches will appear in your Dashboard under Saved.
If you would like to remove a search from your saved searches, simply click on the bookmark icon. Note that this is permanent and cannot be reversed.