If you click on this link, you will see above the search line --Searching: Mental Measurements Yearbook with Tests in Print. This is how you know that you are in the MMY & TIP database.
In general, you can do this by selecting the CHOOSE DATABASE above search line. When you have done that you can then select MMY & TIP.
IMPORTANT: You will need to select Advanced Search
You can select AC Acronym in the Select a Field (Optional) drop down menu. You will have to include an acronym. If you click on the link above, you will see the results for a search using the acronym ADHD.