score:15
The website of Renfe - the national train operator in Spain - also offers only a handful of options for that trip (on the one random date I checked) in June. But if you look at closer dates - say, next week - there are far more trains available.
This is what The Man in Seat 61 (an unofficial but very good resource for train travel almost anywhere trains are operated) has to say on when tickets for Spanish trains become available:
In theory, tickets should go on sale 60 days ahead for all trains other than AVE trains which should open 90 days ahead. However, this isn't exact - Renfe is a law unto itself, and loads dates in large blocks as and when it feels like it, often significantly less than 60 days and often loading some trains before others. If you go online and don't see the complete train service which you're expecting to see, and it's more than a month to go before departure, the chances are that all trains are not yet loaded. Renfe is particularly lax in opening bookings for dates after the timetable changes at midnight on the 2nd Saturday in June and 2nd Saturday in December when the booking horizon can shrink to as little as 30 days.
The final sentence seems especially relevant in your case. Not only is June borderline for the theoretical 60 day horizon, but you may well be looking for tickets after a timetable update - and availability in that case is often delayed.
Upvote:5
In addition to the good answer by Chris H, two more things to keep in mind:
For trains in Spain, you might find your booking experience better with the third party website the trainline (no affiliation). This will also show you fares from the low-cost competitor Ouigo EspaΓ±a, that the RENFE website probably doesn't. However, where RENFEs own trains are not yet shown in the RENFE booking system, they very likely aren't shown in thetrainline yet either.