Storing seeds in vacuum packs

Quick question about storing seeds. Has anybody tried vacuum packing their seeds for extended storage time? I have just bought a pack of bean seeds and the cost was eye watering! The thing is there are far too many seeds for even three years even though the pack says they should be good for 5 yrs I bought a pack two years ago for €14 and they have been very poor at germinating this year so I am trying to help germination rate by better storage conditions vacuum sealing seems a good idea... or is it?