We have seen many shias making dua to their saints, but what their Imams said to them?

Kulayni narrated in his “Usool fi Kafi’ (p 715):

Translation:

1 – Ali ibn Ibrahim – father – Hammad ibn Eesa – Harith – Zurara – Abu Jafar (alaihi salam): Allah Azwajal said: “[Ghafir:60] And your Lord says: Call upon Me, I will answer you; surely those who are too proud for My service shall soon enter hell abased”. He (Imam) said: This is Dua, and the best kind of worship is Dua.  I (narrator) said: (What about verse) “[Tawba:114] most surely Ibrahim was very tender-hearted forbearing”. He (Imam) said: Forbearing that (the one who makes often) dua.

2 – Muhammad ibn Yahya – Ahmad ibn Muhammad – Muhammad ibn Ismail and ibn Mahboob – Hannan ibn Sadeer – Father, which said: I asked from Abu Jafar, alaihi salam: What kind of worship is best one? He said: There is nothing better in the view of Allah than asking and supplicating from Him for things which He have. And there is nothing worse in His view than making arrogance from worshipping Him, and not asking Him for things.