@NaveenKNav
Dont try to get the selector of the items inside..
Can you try getting the selector of that text area shown in the drop down. I believe you should be able to get that.
Once you get that, it would probably show all values under inner text. somewhat like below probably, i had the similar scenario at my end:
that means its recognizing that drop down. then just use that selector in select item activity and type in the value you want in select item. it should work.
Regards
Sonali