If you are taking indoor plants outdoors for sunlight during the day, and you have an insect problem indoors, the former is the cause of the latter unless proven otherwise. As for thrips, the best indoor remedy that is safe and organic is diatomaceous earth. It can be very expensive in small containers with a fancy label on it, but if you can find the raw stuff (it is used in various forms by various industries) then it's literally dirt cheap. I have a monstrous bag, and I'd gladly share if you were closer! I recommend you keeping an eye out for some. Sprinkle it around your soil, and anywhere you see evidence of bugs. It's inert and has no effect on your plants. Just keep it out of your eyes and lungs, otherwise it's very safe. Just messes with the bugs. I also put a scoop into my soil mixture each time I do up a batch before transplants. Bugs have the outdoors! They have no rightful place in my bed, pantry, or medicine patch :)