I just want to ask about prayer. Is there special "Surah" I can say in every "Rak'ah" in "Rak'ahat al Sunnah"?Is there good "Surah" I can say in prayer like "Salat al Fajr" or "al Asr" and the other.

Praise be to Allah, the Lord of the World; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
A praying person can recite any verse of Qur'an or any part of a chapter from the Qur'an in his prayer. This rule is for the commonness of the Command of Allah. Allah Says (interpretation meaning): {…So, recite you of the Qur'ân as much as may be easy for you. …}[73:20]
In fact, every part of the Qur'an contains blessings, cure, and Mercy for the believers. The Prophet also did not confine Muslims to given verses of Qur'an to be recited during obligatory or voluntary prayers. What is reported from the Prophet is that he used to recite certain chapters of Qur'an in certain prayers or sometimes recite some chapters or verses of Qur'an during other prayers, all such narrations prove that reciting them in similar occasions is only a desirable act, not mandatory. It is narrated that the Prophet used to recite during Witr prayer the chapter Al-A'la' (81) in first Rak'ah, Al-Kafirun (109) in second Rak'ah and Al-Ikhlas in third Rak'ah. [Nasaie al-Hakim] Imam Al-Albani graded this Hadith as Sahih.
In Fajr prayer he (sallallaahu 'alaihi wa sallam) used to recite longer Surahs, hence "he (sometimes) recited al-Waaqi'ah (56) and similar Surahs in two Rak'ahs"
He recited from Surah at-Toor (52) during the Farewell Pilgrimage.
Sometimes "he would recite Surah Qaaf (50) or similar Surah [in the first Rak'ah]."
Sometimes "he would recite the shorter mufassal Surahs, such as "When the sun is folded up" [at-Takweer 81]".
Once, he recited "When the Earth is shaken" [Zilzaal 99] in both Rak'ah, so that the narrator said, "I do not know whether the Messenger of Allah forgot or recited it on purpose."
Once, on a journey, he recited "Say: I seek refuge with the Lord of the Daybreak" ]Falaq 113] and "Say: I seek refuge with the Lord of Mankind" [Naas 114].
He also said to 'Uqbah Ibn 'Aamir (): Recite the mu'awwadhatain [113-114] in your prayer, for no seeker of refuge has sought refuge by means of anything like them.
Sometimes he used to recite more than that: "he would recite sixty ayah verses or more" - one of the narrators said, "I do not know whether this was in each Rak'ah or in total."
He used to recite Surah ar-Room [30] and sometimes Surah Yaa Sin [36].
Once, "he prayed the Subh [i.e. Fajr Prayer] in Makkah and started reciting Surah al-Mu'minoon [23] until, when he got to the mention of Moosaa and Haaroon or the mention of 'Isa - one of the narrators was not sure - he started coughing and so made rukoo'."
Sometimes, "he would lead them in Fajr with as-Saaffaat" [77].
"In Fajr on Friday, he would recite as-Sajdah [32] [in the first rak'ah, and, in the second,] ad-Dahr" [76].
He used to make the first rak'ah longer than the second.
His recitation in the two Rak'ahs of Sunnah in Fajr used to be extremely short, so much so that 'Aa'ishah (may Allah be pleased with her) used to say: "Has he recited soorah al- Faatihah or not ?"
Sometimes, after al-Faatihah, he would recite the ayah "Say: We believe in Allah and the revelation given to us..." [Baqarah 2:136] in the first rak'ah; in the second, the aayah "Say: O People of the Book! Come to common terms as between us and you..." [aal-'Imraan 3:64]. Occasionally, he would recite instead of the latter, "When 'Isa found unbelief on their part..." [aal-'Imraan 3:52].
Sometimes he would recite Surah al-Kaafiroon [109] in the first rak'ah, and Surah al-Ikhlaas [112] in the second; also, he used to say: what an excellent pair of Surahs they are! He heard a man reciting the former Surah in the first rak'ah, so he said, "This is a slave who believes in his Lord". "Then the man recited the latter Surah in the second rak'ah, so he said, "This is a slave who knows his Lord".
As for Zuhr prayer, "He (sallallaahu 'alaihi wa sallam) used to recite al-Faatihah and two Surahs in the first two Rak'ahs, making the first one longer than the second."
Sometimes he would lengthen it to the extent that "the Zuhr prayer would have started, and someone could go to a plain: al-Baqi,' fulfil his need, [come back to his place,] make his ablution, and then come (to the mosque) while the Messenger of Allah (sallallaahu 'alaihi wa sallam) was still in the first rak'ah, it was that long". Also, "they used to think that he did so to allow people catch the first rak'ah."
"He used to recite in each of these two rak'ah about thirty aayaat, such as al-Faatihah followed by Surah as-Sajdah [32]".
Sometimes he would recite "By the Sky and the Night-Visitant" [Taariq, 86], "By the Sky, (displaying) the Constellations" [Burooj, 85], "By the Night as it conceals" [Layl, 92] and similar Surahs."
Occasionally, he recited "When the Sky is rent asunder" [Inshiqaaq 84] and similar ones.
"They could tell that he was reciting in Zuhr and 'Asr from the movement of his beard. As for 'Asr prayer: "He used to recite about fifteen aayaat in each of the first two Rak'ahs, about half as much as he recited in each of the first two Rak'ahs of Zuhr, and he used to make the last two Rak'ahs about half as long as the first two ones".
As for Maghrib prayer, "He (sallallaahu 'alaihi wa sallam) used to (sometimes) recite the short Surah", so that "when they had finished praying with him, they could go away and (it was possible to) shoot an arrow and see where it landed." Once, "while on a journey, he recited "By the Fig and the Olive" [Teen 95] in the second rak'ah."
But sometimes he would recite the long or medium mufassal Surahs, hence "he would recite "Those who disbelieve and hinder (men) from the Path of Allah" [Muhammad 47];" or Surah at-Toor [52]; or Surah al-Mursalat [77], which he recited in the last prayer he prayed.
Sometimes "he would recite the longer of the two long Surahs [A'raaf 7] [in two Rak'ahs]." Or he would recite al- Anfaal [8] in two Rak'ahs.
Imam Ibn al-Qayyim said: 'The Prophet was not restricted to recite certain Surah in any prayer except the prayer of Jumua and feasts (Eid), he used to recite in those prayers Al-'Al'a (87) in the first Rak'ah and Al-Ghaashiyah (88) in the second Rak'ah".

Allah knows best.