Witr and Nawaafil

Doing Istikharah to find out the truth

Q: Can I do istikharah for knowing the truth or is there any dua for revealing the truth?

Recently, I have been stuck into some confusions and doubts about my partner. But I really don't know if he is telling the truth or not. I saw many hints that's why I just cannot put trust on him. It's killing me inside. I cannot concentrate in my daily work. I don't know if it's true or shaytan is making me think things? So I badly want to know the truth so that I can stable my mind and move on. Is there any solution or any dua?

Tahajjud, Isharaaq, Chaasht and Awwaabeen Salaah

Q:

1. How many rakaats can I pray for Tahajjud, without including witr?

2. How many rakaats of Ishraaq can I pray, and when is the time for Ishraaq?

3. When is Chaasht prayer time if Zuhr is at 12:41? And how many rakaats should I pray for Chaasht Salaah?

4. As for Awwaabeen Salaah, how many rakkats can I pray?

Please include any mustahab surah’s that I should recite in the rakaats. e.g. For Ishraq first rakaat, recite Ayat-ul-kursi, and for the second rakaat, recite Surah Ikhlaas. 

Performing the sunnah muakkadah salaah before and after the zuhr salaah

Q: Today, my Moulana told us that if we did not read the full 12 rakaats of Zuhr Salaah, then we should go and read it. I had only read the 4 fardh and I was rushing a lot. We were writing our Jamiatul Ulama exams so I thought that if I go to read the sunnats, then I will have less time to write the paper, so I lied to my Ustaad and did not go to read the sunnats. Now I am feeling bad for deceiving and lying to my Ustaad. Will I be sinful if I leave out performing the sunnats?