Remember these intersecting circles from High School Geometry? They're BACK! It's a Venn Diagram. Think about the words you search as being in a Venn Diagram. That can help you form effective searches in library resources (pssst, and Google too!).
See the capitalized words (AND, OR, AND NOT)? These are called Boolean operators. In resources like the library databases, the library catalog, and Google, you can use those words to narrow or broaden your search.
Here are a few searches you may want to try:
music AND secondary NOT primary
music AND therapy NOT adults
MORE SEARCH TIPS:
Once you have a citation for an article or a book, whether you found it in a database or a bibliography or cited in an article, what do you do next?
Feel free to ask your friendly music librarian for assistance!