LINQ Query

 List filteredListOfFocusAreas = new List();

                    foreach(var segment1 in  segment1Value.Split(';'))

                    {

                        var segment1DBValue = 1; //Fetch mapped value from DB in INT

                        foreach(var segment2 in segment2Value.Split(';')){

                            var segment2DBValue = 1; //Fetch mapped value from DB in INT

                            filteredListOfFocusAreas.Add(listOfFocusAreas.Where(fa => fa.Segment1 == segment1DBValue && fa.Segment2 == segment2DBValue && fa.Segment3 == 0));

                        }

                    }