Get Issue Details by custom fields other than Key and ID by JIRA REST API

Hi All,
I am new to Jira REST API. We are trying to migrate the content from Clear Quest to Jira.
we have migrated content using CSV Import , So all our issue defectIDs are migrated to ReferenceID(Custom Field) in Jira. Now planning to consume Jira REST API to get the issue details by using Reference ID or other fields.
Pls let me know - Is this possible ? If yes pls give me some idea and i am trying it from C# code.

Thanks
Vishnu

You need to do it in two phases - do a /rest/api/2/search request, then a subsequent /rest/api/2/issue request to retrieve full details if you didn’t retrieve them in the search request.

Thanks for your reply. will try and let you know…