Nejati's film won the best patriotic film award while Hajiha's flick took the special jury award at the festival's 10th edition, IRNA wrote.
Alireza Shahrokhi, a member of the festival's panel of jury, said that 30 films participated in four sections of documentary, artistic films, animations and short videos.
He added that Iranian films were highly welcomed by the audience earning a special status among the movie lovers.
'It Rains slowly' is set in Turkey just before the coup d’état of 1980, narrating the story of a teacher who teaches his students about freedom and how to resist injustice.
'Kinoman' (In Love with Cinema) won Grand-Prix at the festival.
The panel of jury at the festival was headed by Russian film critic Kirill Razlogov.
The 10th edition of the festival was held from September 4 to 6 in Kazan, southwest Russia.