Modify the forcefield

Dear colleagues,

In these days, I'm trying to modify the forcefield which is supported by Accelrys, Dreiding force field.

When I open the force field file, the van der waals tab has no information so as to electrostatics.

However, when I calculate the energy of molecule using forcite module using various force fields, the results always contain van der waals and electrostatic energy.

How can I modify these parameters in the forcefield manager tab?

Sincerely, Kim