Try puttin 'Me!' in front of each controlname as below:
Private Sub save_Click()
CurrentDb.Execute "Insert into Full_Details(Col1,col2,col3,col4,col5) Values ('" & Me!Combo0 & "','" & Me!Combo1 & "','" & Me!Combo2 & "','" & Me!Combo3 & "','" & Me!Combo4 & "');"
MsgBox "Record Saved !!!"...