Yea, if they put through inquiries around the same time it all counts as one inquiry. It's probably the lack of credit.
You can fix this with a prepaid CC as mentioned. Use it for reoccurring monthly cost and pay off every month. It's not enough to use it every now and again. Even a couple/few per month make a difference.
You can also buy something on credit, like a mattress or laptop. I'm sure plenty of people get uppity about spending in this way. However,to build your credit you have to pay to play. If you're looking into a new bed, computer, or other tools you would have bought anyway this choice is a reasonable sacrifice to get ahead. Note i said, "tools". If you're going into debt for it make sure it's a proper investment. This is not an excuse to buy a new home stereo, SUV, or musical instrument, unless you're gigging and making money from it.