The word(s) "concerning" appears 137 time(s) in 127 verse(s) in Quran in Muhammad Pickthal translation.

(41) And We verily did allot unto the Children of Israel a fixed abode, and did provide them with good things; and they differed not until the knowledge came unto them. Lo! thy Lord will judge between them on the Day of Resurrection concerning that wherein they used to differ.

(42) And if thou (Muhammad) art in doubt concerning that which We reveal unto thee, then question those who read the Scripture (that was) before thee. Verily the Truth from thy Lord hath come unto thee. So be not thou of the waverers.

(43) Lo! those for whom the word of thy Lord (concerning sinners) hath effect will not believe,

(44) Is he (to be counted equal with them) who relieth on a clear proof from his Lord, and a witness from Him reciteth it, and before it was the Book of Moses, an example and a mercy? Such believe therein, and whoso disbelieveth therein of the clans, the Fire is his appointed place. So be not thou in doubt concerning it. Lo! it is the Truth from thy Lord; but most of mankind believe not.

(45) Who doeth greater wrong than he who inventeth a lie concerning Allah? Such will be brought before their Lord, and the witnesses will say: These are they who lied concerning their Lord. Now the curse of Allah is upon wrong-doers,

(46) They said: O Salih! Thou hast been among us hitherto as that wherein our hope was placed. Dost thou ask us not to worship what our fathers worshipped? Lo! we verily are in grave doubt concerning that to which thou callest us.

(47) So be not thou in doubt concerning that which these (folk) worship. They worship only as their fathers worshipped aforetime. Lo! we shall pay them their whole due unabated.

(48) And we verily gave unto Moses the Scripture, and there was strife thereupon; and had it not been for a Word that had already gone forth from thy Lord, the case would have been judged between them, and lo! they are in grave doubt concerning it.

(49) O my two fellow-prisoners! As for one of you, he will pour out wine for his lord to drink; and as for the other, he will be crucified so that the birds will eat from his head. Thus is the case judged concerning which ye did inquire.

(50) Go, O my sons, and ascertain concerning Joseph and his brother, and despair not of the Spirit of Allah. Lo! none despaireth of the Spirit of Allah save disbelieving folk.