When user put her/his mouse pointer over omitted graph title, entire title pops up. 

I add CSS feature in mouseover function and mouseout function.

$("#" + graphId).mouseover(function(event) {
			if (!isShort) {
				return;
			}
			var target = event.target;
			if ($(target).hasClass("dygraph-title")) {
				$(target).text(tmpTitle);
				$(target).parent("div").css('z-index',"1");
			}
		});
		$("#" + graphId).mouseout(function(event) {
			if (!isShort) {
				return;
			}
			var target = event.target;
			if ($(target).hasClass("dygraph-title")) {
				$(target).text(optionSettings.title);
				$(target).parent("div").css('z-index',"0");
			}
		});