the Bosch sanders come w/ an adapter...I agree with Chuck and here is what you need to connect from your sander to your shop vac. You also need some radiator clamps with thumb screws to keep the ends attached to your sander. I don't know if Rockler ships to where you live but I hope so.
Dust Right® Universal Small Port Hose Kit | Rockler Woodworking & Hardware
This works on so many small power tools.