There is no contains filter
URI Conventions (OData Version 2.0)
http://www.odata.org/documentation/odata-version-2-0/uri-conventions/Use OData query operations in SharePoint REST requests
https://msdn.microsoft.com/en-us/library/office/fp142385.aspx
Search has different syntax
SharePoint Search REST API overview
https://msdn.microsoft.com/library/8a4f7863-e4c1-4099-9189-a1894db36930%28office.15%29.aspxhttps://docs.microsoft.com/en-us/sharepoint/dev/general-development/sharepoint-search-rest-api-overviewFAST Query Language (FQL) syntax reference
https://msdn.microsoft.com/en-us/library/office/ff394606.aspx
