Here are a few things I do to catch those fussy fish. When bait fishing I drift a worm, hooked through the head, on a small hook with just a single split shot a foot or so up the line. Let it drift and tumble down the runs and pools naturally.
Keep a close eye on your line for a light pull or sideways movement. At the least movement or tautness, set the hook. Don?t worry about snagging and breaking off, you?re only loosing a hook and you should have lots of them with you.
When fly fishing and those fussy fish just won?t take.
I put on a small bit of worm on the hook and retrieve slowly just under the surface. If fishing a run let it drift to the end keeping the line taunt as possible and be ready to strike. The worm odour makes the fish hold just a little longer, giving me a chance to set the hook.
When a lure is not producing try changing its action by slightly bending it or the front blade. I find that the change in action will get those fussy boys moving...