I'm probably doing something really dumb here, but it's driving me crazy.
I have two PyDev projects in Eclipse. One project, 'Analysis' depends on the other, 'PyCommon'. I'm 100% sure of this as when I look at the project references for Analysis, PyCommon is checked, and automatic import/code completion works when I reference elements in PyCommon from Analysis.
I'm trying to write/run a module in Analysis. The module is fhb/analysis/log_parsers.py.
I'm trying to import the element OrderStatus from fhb/pycommon/types/order_status in the PyCommon project. So, my import statement is 
'from fhb.pycommon.types.order_status import OrderStatus'
PyDev clearly knows where this is because that import statement was written automatically by PyDev on a quickfix correction. Nonetheless, when I try to run the main function in log_parsers.py, I get this:

Traceback (most recent call last):
   File "/workspace/Analysis/src/fhb/analysis/log_parsers.py", line 6, in 
     from fhb.pycommon.types.order_type import OrderType
  ImportError: No module named pycommon.types.order_status

All of these packages are under a proper source folder ('src') in each project.
Also, even though Analysis absolutely is set to reference PyCommon , when I look under PyDev-PYTHONPATH in Analysis's properties, only Analysis's own src folder appears under the 'Source Folder' tab, and it's the only project I see if I click on 'Add source folder'
Your problem may come from __init__.py being missing from some of your module folders. 
For your example, for using OrderStatus from order_status.py in fhb.pycommon.types.order_status, you need to have a (possibly empty) __init__.py file in fhb, fhb/pycommon, and fhb/pycommon/types.
Also note that for pylint to work correctly for fhb/analysis/log_parsers.py, you need to have an __init__.py in fhb/analysis as well.
Can't import module from dependent project in PyDev