Bash, get values from json file, all in one line

I would just split the file into one entry per line first. That makes parsing it much simpler. So, find all cases of },{ and add a newline breaking them:

$ sed 's/},{/},\n{/g' file
{ "article": {"code": "01333457004","name": "ALAZANIS VALLEY 2015","note": "ČERV VÍNO EVROPA VÝCH OSTATNÍ","sel_unit": "Kus","unit_price": 229.0,"category": "ČERVENÉ,POLOSLADKÉ","unit": "L","EAN": "4867601700052","unit_volume": 0.75,"producer": null,"tax": 21.0,"text": "Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;","is_action": "1","action_from": "20190905","action_to": "20190918","ordered_from": "20190126","ordered_to": "20190830","shelf_id": "1030542","is_outlet": 0}},
{ "article" ...

Now, you can just search for your code. But use the -w flag for grep which makes it look for "words" to avoid finding the code as a substring. So if you have one line with code 01333457004 and another line with code 013334570041, searching for 01333457004 won't find 013334570041.

Putting all this together gives:

$ sed 's/},{/},\n{/g' file | grep 01333457004
{ "article": {"code": "01333457004","name": "ALAZANIS VALLEY 2015","note": "ČERV VÍNO EVROPA VÝCH OSTATNÍ","sel_unit": "Kus","unit_price": 229.0,"category": "ČERVENÉ,POLOSLADKÉ","unit": "L","EAN": "4867601700052","unit_volume": 0.75,"producer": null,"tax": 21.0,"text": "Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;","is_action": "1","action_from": "20190905","action_to": "20190918","ordered_from": "20190126","ordered_to": "20190830","shelf_id": "1030542","is_outlet": 0}},

If you really want to do it in a single operation, you can try using grep with -P for PCRE regular expressions which support lookaheads:

$ grep -oP '{ "article":.*?\b01333457004\b.*?}(?=,{)' file
{ "article": {"code": "01333457004","name": "ALAZANIS VALLEY 2015","note": "ČERV VÍNO EVROPA VÝCH OSTATNÍ","sel_unit": "Kus","unit_price": 229.0,"category": "ČERVENÉ,POLOSLADKÉ","unit": "L","EAN": "4867601700052","unit_volume": 0.75,"producer": null,"tax": 21.0,"text": "Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;Alazanis Valley 2015;Gruzie,Kachetie;červené polsladké;750ml;16°C;","is_action": "1","action_from": "20190905","action_to": "20190918","ordered_from": "20190126","ordered_to": "20190830","shelf_id": "1030542","is_outlet": 0}}

This will look for { "article":, then the shortest stretch of 0 or more characters (.*?) until the string 01333457004, but only if that appears surrounded by non-word characters, so only if it is a word; that's what the \b mean, then the shortest stretch of 0 or more characters again that end with a } followed by ,}.

You can use jq.

Have a look at this

Probably in your case it should be something like:

cat test.json | jq '.[] | select(.article.code | contains("01333457004"))'