Export results into a PST

After performing a search that goes across a dozen .pst files I need to save the results into a new .pst file. How can I do this? I have experimented using export but PST is not a format choice and select "Other" and entering PST just makes a text file that is not useable. I am using the trial version but if I can't export or save the results to .pst then I don't see how I can use this in the future.

The actual search is great I just need help saving the results in PST formatting if possible.

---