I got multiple entry schengen visa issued by Greece. Can I directly travel from India - Qatar - Romania or through schengen state

As per the website of the Romanian Ministry of Foreign Affairs:

Romania acknowledges as being equivalent to its own national visas, for transit and for stays up to 90 days per period of 180 days the following:

• The two or multiple entry short-stay visa issued by a Schengen member state;
• The limited territorial validity visa issued by a Schengen member state;
• The short-stay visa issued by Bulgaria, Cyprus or Croatia;
• The long-stay visa issued by a Schengen member state;
• The long-stay visa issued by Bulgaria, Cyprus or Croatia;
• The residence permit issued by a Schengen member state;
• The residence permit issued by Bulgaria, Cyprus or Croatia
• The long-term resident's EC residence permit (the validity of which is of 5 years or more) issued by a member state of the European Union.

This website further adds that the number of entries or the validity period on the alternate visa should not have been exhausted. As per this, it seems like your multiple entry Schengen visa is valid for entering Romania. However, you may wish to confirm this by directly contacting your nearest Romanian foreign mission.