[Air-L] About estimation of quantity of Tweets per keyword

[Xanat Meza]

Hello everyone,
I know that this question might not have an answer given the changes Twitter has gone through in the last year, but I thought it was worth a shot.
Is there any online tool that could estimate the quantity of Tweets containing a keyword within a specific time frame? 
Regards,
Xanat V. Meza

Ph.D. Kansei, Behavioral and Brain SciencesUniversity of Tsukuba
M.A. Media and Communication
Yeungnam University
B.D. Graphic Communication Design
Universidad Autonoma Metropolitana