'There were no workhouses in the 1930s. They were abolished under the Local Government Act of 1929 and became Public Assistance Institutions, so you will need to use those keywords when searching.'
My aunt and uncle ran one from 1930's to 1970's. After he died around 2010, I visited the town and asked for directions to the infirmary/old people's home/hospital. 'Oh, you mean the workhouse' was the response from a local.