have a bunch of pea sized cubed meat or cheese bits, really good quickly eaten non crumbling treats. sit on the floor, put the toy in ur reach and click/treat for any touch of the toy accidently or on purpose. point to it and touch it. you are teaching targeting basically. as the dog learns what gets a click up the criteria when you can place it on the ground or hold it in ur hand and the dog touches or noses it.
keep it short, if she loses attention pick it up and place it behind your back. do some other tricks whee have fun and praise and treats and put the toy back down. smear it with food to encourage touching with nose if you need to. click treat every touch for a while. don't say a word. then up the criteria and she needs to move it, then pick it up even if she drops right away. then pick up for longer. then put arms reach and she must move it toward you after picking it up before she drops it.
work up time and distance and you've shaped the come behavior. if you aren’t familiar with clickers there are tons of great books. i would start with
www.clickertraining.com.
forgot to add use a toy that is interesting to the dog, a squeeky or plush that is not edible so won't compete for the treats. understand too some dogs don't like fetching but love other things like tug. use what the dog likes to get something similar you do want. thowing a favorite tuggy may elicit a fetch for more tugs.