The FHIR API ValueSet search by name parameter only accepts FHIR value set names, it does not accept VSAC value set names. You can find the VSAC Name, FHIR Name and FHIR Title in the VSAC user interface for any value set OID. Here is an example in which you can see the VSAC Name, FHIR Name and FHIR Title in our VSAC web browser user interface: https://vsac.nlm.nih.gov/valueset/2.16.840.1.113762.1.4.1047.611/expansion/Latest

• The VSAC value set name is mapped to the FHIR "title" field. Therefore, a FHIR API ValueSet search by title={VSAC value set name} shall return results if the VSAC value set name exists.
• However, if a FHIR API ValueSet search uses name={VSAC value set name}, a total of 0 results shall be returned.

• Search by name = {FHIR value set name}: The following API call shall return "total": 1 and "entry"."resource"."name": "N3MirrorGoldmannExam"
  https://cts.nlm.nih.gov/fhir/ValueSet?name=N3MirrorGoldmannExam
• Search by name = {VSAC value set name}: The following API call shall return "total": 0
  https://cts.nlm.nih.gov/fhir/ValueSet?name=3 Mirror Goldmann exam
• Search by title = {VSAC value set name}: The following API call shall return "total": 1 and "entry"."resource"."name": "N3MirrorGoldmannExam" and "entry"."resource"."title": "3 Mirror Goldmann exam"
  https://cts.nlm.nih.gov/fhir/ValueSet?title=3 Mirror Goldmann exam

See our Capability Statement for the VSAC-to-FHIR mapping of VSAC Value Set Name, FHIR Value Set Name and FHIR Value Set Title.