The word(s) "deeply" appears 7 time(s) in 7 verse(s) in Quran in Mohsin Khan translation.

(1) Those who remember Allah (always, and in prayers) standing, sitting, and lying down on their sides, and think deeply about the creation of the heavens and the earth, (saying): "Our Lord! You have not created (all) this without purpose, glory to You! (Exalted are You above all that they associate with You as partners). Give us salvation from the torment of the Fire.

(2) He it is Who has appointed for you the night that you may rest therein, and the day to make things visible (to you). Verily, in this are Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) for a people who listen (i.e. those who think deeply).

(3) (Allah) will say: "Like this: Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) came unto you, but you disregarded them (i.e. you left them, did not think deeply in them, and you turned away from them), and so this Day, you will be neglected (in the Hell-fire, away from Allah's Mercy)."

(4) Do they not think deeply (in their ownselves) about themselves (how Allah created them from nothing, and similarly He will resurrect them)? Allah has created not the heavens and the earth, and all that is between them, except with truth and for an appointed term. And indeed many of mankind deny the Meeting with their Lord. [Tafsir At-Tabari].

(5) It is Allah Who takes away the souls at the time of their death, and those that die not during their sleep. He keeps those (souls) for which He has ordained death and sends the rest for a term appointed. Verily, in this are signs for a people who think deeply.

(6) And has subjected to you all that is in the heavens and all that is in the earth; it is all as a favour and kindness from Him. Verily, in it are signs for a people who think deeply.

(7) Do they not then think deeply in the Qur'an, or are their hearts locked up (from understanding it)?