Attracting forces

I was taught that force can only be applied positively (eg. a vacuum does not suck, the pressure differential pushes towards it). Einstein suggested that the same explanation could be applied to gravity as mass distorts space-time and thus a positive force is applied to push two masses towards each other. Bearing this in mind, why can the strong force, the weak force and the electromagnetic force described as being an 'attraction' between two things? Have I fundamentally misunderstood something here or is it possible that these forces are the result of a similar differential that applies a positive 'push.' It seems to me that if electromagnetism is viewed as a fluid pattern instead of a static field then it could explain why it is so weak with increased distance. I imagine a fan or turbine in an enclosed space, creating a positive and negative side which would generate an airflow of a very similar shape to a magnetic field. Could anyone out there help me understand this better, show me where I am wrong or let me know what research has been carried out that might explain?