What advice could you give to someone like me who always looks into and searches into people's affairs while I think I'm enjoining the good and forbidding the evil?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If people do wrong and you forbid them from doing it, or that they abandon something good and you order them to do it, then you are enjoining good and forbidding evil. There is no doubt that enjoining good and forbidding evil is a matter that concerns you. Moreover, this matter is one of the most recommended obligations for the believers. Allaah Says (what means): {And let there be [arising] from you a nation inviting to [all that is] good, enjoining what is right and forbidding what is wrong, and those will be the successful.}[Quran 3:104]. Allaah also Says (what means): {Enjoin what is right, forbid what is wrong, and be patient over what befalls you. Indeed, [all] that is of the matters [requiring] determination.}[Quran 31:17]. Furthermore, the Prophet said: “Whoever amongst you sees an evil, he should change it with his hand (i.e. physically), and if he is unable to do so, he should change it with his tongue (i.e. verbally), and if he is unable to do so, he should change it with his heart [detest it], and this is the weakest level of faith.”

Imaam An-Nawawi said: 'Enjoining good and forbidding evil is an obligation according to the consensus of the entire Muslim scholars based on the evidences from the Book of Allaah and the Sunnah of the Prophet ; it is also included among the meaning of offering advice, which is the essence of religion. A pubescent person is not exempted from Enjoining good and forbidding evil just because he thinks that it might be of no benefit, rather he is obliged to do so, as reminding benefits the believers.' However, if what you want to be engaged in is not enjoining good or forbidding evil, then this is what the Prophet intended by his saying: “It is among the good morals and character of a Muslim not to involve himself in that which does not concern him.” [Maalik and At-Tirmithi] An-Nawawi said: 'All matters that are of no benefit [a surplus, idle talk…] and learning a science [acquiring knowledge] that is of no benefit are included among the matters that do not concern a person. So it is better for him to abandon it, like the person who abandons a knowledge by which he benefits himself only and opts for a knowledge by which he benefits all other people.'

Allaah Knows best.