If I have a response as follows: 

```
{"id":"140","rsd":null,"col":"green","cc":"B5307F","pn":"KENWAY TYRES RENEWAL 2014","loc":"ABD - LR / L3 / L3","isf":"1","isl":"0","tq":"15","pi":null,"st":"1","dsid":"15","cid":"2120","spl":null,"wid":"WI/3ivdfzhg","inv":null,"pdid":"1103","di":"0","pl":"0"}{"id":"141","rsd":null,"col":"green","cc":"B5307F","pn":"KENWAY TYRES RENEWAL 2014","loc":"ABD - LR / L3 / L3","isf":"1","isl":"0","tq":"15","pi":null,"st":"7","dsid":"15","cid":"2120","spl":null,"wid":"WI/3ivdfzhg","inv":null,"pdid":"1103","di":"0","pl":"0"}

```

and if I need to `check st=7` and `inv=null` and extract only 141 not 140. 

How can I do it? Thanks in advance.