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Can I say,

(i) John felt grateful and thanked the man for help / for helping him.

(ii) John felt very happy and grateful to the man for his help / for help

(iii) John called to the kind man to help him / for help.

(iv) Jonn thanked the kind man for help / for helping him / for his help.
Comments  
(i) for helping.
(ii) happy or grateful, not both; they are the same, so one would be redundant.
(iii) for help; to help means that John wants to help the kind man.
(iv) for his help; the first option lacks a article; the second option (I guess) needs an object complement.
spacedunce-5(i) for helping.
(ii) happy or grateful, not both; they are the same, so one would be redundant.
(iii) for help; to help means that John wants to help the kind man.
(iv) for his help; the first option lacks a article; the second option (I guess) needs an object complement.

"Happy" and "grateful" are not the same. Check them up in a good dictionary...

"John thanked the kind man for helping him" is fine too.