TurboTax cannot "pull" tax returns that were not started using TurboTax.
If the return was started with some other tax preparation software or using a paid tax professional then the tax return should be available from those sources.
Otherwise -
You can also get free transcripts of your federal return from the IRS - http://www.irs.gov/Individuals/Get-Transcript
For a fee of $50 you can get a complete federal tax return from the IRS by completing Form 4506 - http://www.irs.gov/pub/irs-pdf/f4506.pdf
Did you start the return in Turbo Tax? Did you file 2014 somewhere else or not file at all?
How to finish a prior year online return https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-started-in-turbotax-online/00/26322
TurboTax does not support tax year 2014.
If you started a 2014 tax return using TurboTax then the PDF download will only have the forms and schedules that are required to file a tax return. There will not be any worksheets or information only pages in the PDF.
To access your current or prior year online tax returns sign onto the TurboTax website with the userID you used to create the account - https://myturbotax.intuit.com/
Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show. Click on the Year and Click on Download/print return (PDF)
confusing message -what documents are you seeking since you say you can access your 2014 return?
neither TT nor any other self prepared return software has the source documents. you do or should such as w-2's. all the tax returns would contain is the info you entered.