When searching within an EBSCO database, click on the Choose Databases option to find additional databases you can add to your search. A box will pop up allowing you to choose those databases, then click on the OK button to add them.
When searching within a Proquest database, you will see the number of databases you are currently searching provided at the top of the page. If you are searching only one database, then it will say Change Database where the number would be. Click on the number of databases link or on Change Databases to see other database options. You can then check off the databases you would like to add to your search. Once done, click on the Use selected databases button.
Once you have added additional databases to a search, you can then start searching. Please note that some search options may change. Different databases may have different search options, even when they come from the same vendor. You may lose some search options or you may be able to apply certain search options to only a few of the databases.