Question on how to do a lookup

[spartan1685]

hey all,
I am trying to figure out how to do this one part of my excel sheet.
I have roughly 5k in rows containing unique info. I assigned a unique letter to each group ie aa, b, ccc, etc. and each name in the group gets a numerical value 1, 2,3, etc
I first ask for the user to input a department then input a group.
If they give me that information how can i lookup in that particular group to display user names. so say in group x there are 5 names and i want to give the user a drop down to let them choose one of those 5. any thoughts?
i greatly appreciate help in advance...

 

[spartan1685]

if this helps basically in sheet 1: G7 the group and divsion concatenated so it looks like this: waterdivtreatgroup, in sheet2 where i house all of the data this name is in the a column for any individual in this group.. I need to create a drop down off of this name waterdivtreatgroup so it can display the listing of names under this term.
i really dont even know how to explain / start this problem very well...
currently i have a countif and i know how many times the object appears in sheet2. now i need to actually lookup the names under that object...or if it was possible to get either the start or end cell location i could do the drop down off of those i suppose...

 

[dr_shivan]

You can do a filter and filter those entries which is the most simplest way to do