IF you have a search term in the Search field, then only those records that matched the search query would be returned. So click the little (x) button on the right side of the Search field to clear the search. The rest of your records should appear again.
My apologies if I’m misunderstanding the issue though. I’m not entirely sure I’ve ever seen this issue before when searching for a record the rest of the database becomes unavailable.
Could it be you’ve disabled the Forms List view? If so, click on Forms List on the toolbar to see your forms again.