Two months after rejecting two bids for a new ferry service between Nova Scotia and Portland, Maine, provincial officials are renewing efforts to restore ferry service for next year. The Nova Scotia Department of Economic and Rural Development and Tourism says it is working closely with the Nova Scotia International Ferry Partnership in the search for a qualified ferry operator. The province has issued a new ‘‘ferry opportunity’’ document outlining what it is looking for, including the criteria for a new operator, details on the process, and background. The proposal submission deadline is June 20. The Nova Scotia government says it is willing to spend up to $21 million in subsidies to set up the operation. There has been no ferry service between Nova Scotia and Maine since 2009.