underweight puppy
 

My puppy is now 6 months and she weights 22lbs and according to the average growth chart she should be around 40lbs
she's thin, i deworm her every 2 months and I feed her 2 cups a day of earthborn primitive natural (grain free), should i increase her food or consider getting weight gainer supplement?

Have you taken her to the vet for a full check up? She should have gone once a month for shots depending on what you go with? Is she eating the food once you place it down? Is it twice a day at that amount or total?

I don't want to get into the whole raw vs kibble but you might want to at least start adding some raw marrow soup bone that you can get at any supermarket for like five dollars for six. Consider changing your food and look into raw also, or a mix. Doesn't seem like she is getting her nutrition for growth.
Did you adopt her, breeder? How is her energy?

She eats it once i put it down and she always wants more after she finishes eating
i feed her one cup in the morning and one at nigh, the chart says according to her current weight i should feed her 1-1/4 to 1-3/4 cups a day
I mix her food with canned food 3 days a week, I can try adding some raw food to her meal
I was feeding her blue buffalo life protection before but she didn't like it so I switched to earthborn and she loves it and i noticed that her coat improved
She's a bit lazy and she doesn't like it much when i take her out

A friend of mine told me to try mvpk9 weight gainer, should I?

You really have to go more by body condition than actual weight as dogs have different frames, sizes, etc. You might try posting a couple of pictures, one from the side and one from the top looking down at her. If you can see her ribs and her hipbones, then instead of buying a weight gain supplement, I would just up her food by a half cup each meal (keep it there for a week or so) and then monitor her body condition.