hey brenden does adding an .And() between them help?
var physicians = DocumentHelper.GetDocuments("custom.people")
.OnCurrentSite()
.Path(PeopleUrl, PathTypeEnum.Children)
.InRelationWith(ValidationHelper.GetGuid(specialty, Guid.Empty), "isrelatedto", RelationshipSideEnum.Right)
.And()
.InRelationWith(ValidationHelper.GetGuid(location, Guid.Empty), "isrelatedto", RelationshipSideEnum.Right)
.OrderBy(new string[] { "LastName", "FirstName" })
.Columns(new string[] { "DocumentName", "NodeAliasPath", "NodeLevel", "NodeOrder", "NodeGuid", "Photo", "FirstName", "LastName", "BioTeaser", "Degree", "PhoneNumber" })
.Published()
.FilterDuplicates();
if not I can test this a bit more with the devs!