Here is a solution I built from the help I got in another thread. Hope it is useful. I thought it was!
It allows you to create a list by filtering for both included items and excluded items. You can remove all items from one list from a second list and also exclude items from a third list.
bigList = {"item1", "item2", "item3", "item4", "item6", "item7",
"item8", "item9"};
excludedElements = {"item1", "item2", "item5", "item6"};
includedElements = {"item8", "item9"};
Select[Select[bigList,
StringFreeQ[#, excludedElements] &],
! StringFreeQ[#, includedElements] &]
Out[14]={"item8", "item9"}
