In Firefox , "Show All History" brings up a separate window showing URLs visited in the past. Those URLs are divided into categories of increasing age, such as "Today" and "Last 7 days". If I enter some text into the "Search History" field then the displayed URLs are limited to those that match the search target and the age category. If I switch to a different age category then the search target is cleared.
My suggestion is to not clear the search target when switching to a different age category, so I don't have to retype the same search target every time the sought item turns out not to be in the current age category.