There are a few basic Sabre commands that work:

All commands start with "1"

Then you enter the date in the form of day followed by 3 letter code for month.

Then you follow it with origin city 3 letter airport code and destination city 3 letter airport code.

If you want a particular time of day enter the hour followed by A or P for AM and PM.

If you want direct flights on a particular airline enter @ followed by the 2 letter airline code.

If you want connection flights on a particular airline enter # followed by the 2 letter airline code.

So, for example, if you want the list to prioritize non-stop American Airlines flights on August 30th around 1pm from SFO to JFK you would enter:

130augsfojfk1P@aa

Note that Sabre will always just prioritize what you have asked for, and then also include other things (like connections, other times, etc.)

If you want to force a connection through a particular city add that code at the end. So for instance to get all AA flights from SFO to LGA connecting in St. Louis leaving SFO around 1pm try this:

130augsfolga1pstl

If you want flights arriving at a particular time add /time to the end. So for example:

130augsfojfk/230p

will give you flights from sfo to jfk arriving around 2:30 pm.

If you want to look at a particular fare bucket modify the ending as -F (where F is the bucket)

So 130augsfojfk-f will give you F bucket availability from SFO to JFK on August 30th.

If you want to check return flights on a later date enter 1R followed by the return date. So after the above command

1R14SEP would give availability from JFK-SFO on September 14th.

Enjoy!

P.S. I forgot to add if you want to check U on Qantas for instance, just do this:
130augsydlax-u

which will check U bucket for SYD-LAX on August 30th.