I want a job to do design optimization using FEA.

FEA: Finite Elemement Analysis. It is difficult since most of the suitable jobs require US citizenship.

A 大专生 就可以 Use CAD software (AutoCAD, SolidWorks, ProENGINEER, etc.) to design and draft something. So employers don't want to spend more on a PhD to do the same design job.

My job searching strategy was wrong, I have not yet searched the employers who only use ProENGINEER.