EBSCO provide a wide range of support tutorials (http://support.ebsco.com/training/tutorials.php) on all facets of their EBSCOHost search interface. Including:

Introduction to EBSCOHost

https://connect.ebsco.com/s/article/Introduction-to-EBSCOhost-Tutorial?l...

Basic Search

https://connect.ebsco.com/s/article/Basic-Searching-on-EBSCOhost-Tutoria...

Advanced Search Single Find

https://connect.ebsco.com/s/article/Advanced-Searching-on-EBSCOhost-Tuto...