Have you tried fresh or live bait ?
Sounds to me like the lures you have tried simply don't match the hatch. If there is plenty of food around for the fish then they will not take a lure that looks different to what they are eating. If you can see schools of fish then chances are they have gathered together to feed. If you cannot work out what they are feeding on then you will need to present them with something they cannot resist.
Try cooked prawn
itsaboat mate...Life is just a boat and then ya marry one !