Westlaw and Lexis Advancehave All in One search boxes, so you can search all the content at once. Then, you can use filters on the left side to narrow to a particular type of content, such as cases.
FInd by Citation: If you have a citation to a case or other document, just type it into the search box - this works on all three systems.
Start typing in the name of a source in the search box
OR Click on Browse Sources in the upper right.
If you have a particular source in mind which you want to search, say Ohio Jurisprudence or Ohio Revised Code:
Type a few letters of what you're looking for into the search bar, e.g. type Ohio Jur.
OR use the browse widget to drill down to the source you want.