Feature selection | sequential search heuristic measure

Hi,

I have a dataset with 33 features (F1-F33) and a class label. I then calculate the feature-class correlations and the feature-feature correlations using the rank correlation node. Then I calculate a metric using math formula and group by. This is calculated on the entire dataset though. I want to loop through and find the best combination of features that yield the maximum metric. I used feature selection loop as a start, but I cannot use a math formula as the inport to the feature selection loop end. Some sort of a sequential search would be best. Any tips would be greatly appreciated!