Refunds are based on having more tax withheld from your paychecks than your tax liability, and on refundable credits that you might be eligible for. You have not mentioned any credits that you could be missing out on, like child tax credit. If you end up not owing anything, but not getting a refund, that means you did things "just right" and did not give the government an interest free loan all year.
But if you want the employer(s) to withhold more tax so that you get a refund, change your W-4.
https://turbotax.intuit.com/tax-tools/calculators/w4/
https://www.irs.gov/individuals/tax-withholding-estimator
https://www.irs.gov/pub/irs-pdf/fw4.pdf
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
