You may have created a large number of forms and now want to search a specific form. You are able to do so by filling out the form name in the white box stating 'Search...':
If you search in 'All forms', you are searching forms of all categories. If you search in a specific category, such as 'Email satisfaction', the search is only for forms within that category.
Please note: you cannot search forms on form ID. A form ID is a code behind the form name, such as 'jQKnLu'.