Pest Insects eating Pear Fruit Tree

wouterkalle1 starts with ...
What is eating my pears? I have two european pears (Doyenne du Comice and Bonne de MAlines). they both get attacjed by something that eats their leaves/destroys their leaves/attacks them when they are still in bud. Especially the Bonne is attacked and hasn't grown much. The Doyenne was ok in year one but now suffers as well. The Bonne was planted first and though they are some 10 meters apart they seem to affect each other.
I have tried Dipel and eco oil. I cannot find any of the culprits on the leaves, no caterpillars, no aphids, no nothing though mites is still a possibility (haven't checked under the microscope (next step).
HAs anyone encountered this problem? See pictures of the Bonne.

Pictures - Click to enlarge
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