Can anyone recommend me any manga that is heart wrenching to read like ao no flag, blue lu...

http://www.mangago.zone/read-manga/tamayura_yuki_ringo/
http://www.mangago.zone/read-manga/hybrid_child/
http://www.mangago.zone/read-manga/hatsukoi_wa_gunjou_ni_tokeru/
http://www.mangago.zone/read-manga/kanemochi_kun_to_binbou_kun/
http://www.mangago.zone/read-manga/lovers_doll/
http://www.mangago.zone/read-manga/konbini_kun/

http://www.mangago.zone/read-manga/mahoroba_no_hibi/

http://www.mangago.zone/read-manga/j_no_subete/ - Quite lengthy

http://www.mangago.zone/read-manga/itou_san_kuraka_sui/

http://www.mangago.zone/read-manga/sorekara_kimi_wo_kangaeru/ - Short stories, some cheery, some very much not

http://www.mangago.zone/read-manga/jigoku_meguri/

http://www.mangago.zone/read-manga/inu_to_tsubame/

http://www.mangago.zone/read-manga/sakura_gari/

http://www.mangago.zone/read-manga/thank_you_my_god/

I tried to leave a reply and it didn't work for some reason, so trying again:

http://www.mangago.zone/home/mangalist/103408/?filter=&page=3

http://www.mangago.zone/read-manga/sakura_gari/

http://www.mangago.zone/read-manga/g_senjou_no_neko/

http://www.mangago.zone/read-manga/j_no_subete/ - Very lengthy one

http://www.mangago.zone/read-manga/mahoroba_no_hibi/

http://www.mangago.zone/read-manga/jigoku_meguri/

http://www.mangago.zone/read-manga/inu_to_tsubame/

http://www.mangago.zone/read-manga/sorekara_kimi_wo_kangaeru/ - Multiple stories, some cheery, some not

http://www.mangago.zone/read-manga/itou_san_kuraka_sui/

http://www.mangago.zone/read-manga/sono_kuchibiru_ni_yoru_no_tsuyu/

Of course the first one showed up afterward...