If you do not know what type of index you are using, you cannot use it effectively. A defendants' index to court records typically only indexes the name of one defendant per court case. The same is usually true for a plaintiffs' index. Grantors indexes to deeds usually indexes the name of just one grantor. All of these records contain the names of other people in a variety of capacities. Most of the indexes to local records are not everyname indexes.
If you do not know what you are using, then how do you know how to use it?