in the AFTERUPDATE event of the combo, put that column value into a hidden text box.
Then the query can read the textbox.
'in VB , columns begin with zero, so column 2 is: cboBox.column(1)
Code:
sub cboBox_Afterupdate()
txtBox = cboBox.column(1)
end sub
query:
select * from table where [field]=forms!fMyForm!txtBox