Google offers desktop search users the options to filter their results down to within a certain range of time or webpages that list their query verbatim. Now, these search tools are available on mobile search.
Users on the Google mobile app or on the mobile website can find them at the far-right position of the results categories bar. Tapping on Search Tools will bring down two parameter droplists.
One is for time, which limits listings to from within the past hour down to from within the past year. Unlike in desktop search, there's no option to put in a custom date range. The other list will let you turn on verbatim search.