Retrieving HST ACS FLT and RAW files

Hi,

I am trying to find and download all the FLT and RAW files of Hubble Space Telescope observations using astroquery.mast. The calibration level for these files is 0 (RAW) -- 2 (FLT). However, when I use astroquery I can only find the calibration level 2 files for some instruments (WFPC/WFC, NICMOS, WFC3) not ACS. Here I attach a minimal reproducible example.

```
import numpy as np

from astroquery.mast import Observations
c = coordinates.SkyCoord(186.75795, +33.55426, frame='icrs', unit="deg")

obs_table = Observations.query_criteria(coordinates=c, radius=0.5,
calib_level=2, obs_collection="HST")
set(np.array(obs_table["instrument_name"]))

```

Output:

{'COS/NUV',
'FOS/BL',
'FOS/RD',
'NICMOS/NIC2',
'NICMOS/NIC3',
'STIS/CCD',
'WFC3/IR',
'WFC3/UVIS',
'WFPC/PC',
'WFPC/WFC',
'WFPC2',
'WFPC2/PC',
'WFPC2/WFC'}

However, I know from MAST webpage [that there are ACS/WFC observations in that region](https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html?searchQuery=%7B%22service%22%3A%22CAOMDB%22%2C%22inputText%22%3A%22186.75795%2033.55426%20%22%2C%22paramsService%22%3A%22Mast.Caom.Cone%22%2C%22title%22%3A%22MAST%3A%20186.75795%2033.55426%20%22%2C%22columns%22%3A%22*%22%2C%22caomVersion%22%3Anull%7D). What I am missing? Thank you
Alex

----

Start with the minimal astroquery.mast example and compare its query_criteria results with the linked MAST portal search for the same coordinates and calibration levels. Trace how ACS observations and FLT/RAW products are represented in the MAST query, then verify that the corrected query can find and retrieve those files.

Written by the indexing model from the issue text.