Ed needed a magic sensing skill, but he did not believe he would be enlightened just because he existed.
'I am not some sort of miracle protagonist' He had gotten pretty lucky thus far but surely not to the extent of a protagonist right? It wasn't as though he would in the next few second suddenly- Ah!
'That's it!' He should give up completely!
The fruit was the only hint they had but he was incapable of locating it. What a pity.
Even if he couldn't miraculously learn the necessary skill, Ed could still try to check his bag of tricks. He had plenty of magic devices that performed a variety of different purposes.
Entering the system space and the divine white storeroom however Ed quickly realized that he really was out of luck.
'I have a hook shot but how's that going to help?' The number of magic devices he collected were little. In fact, a lot of them still came from the time he was with the lich.