a strong feeling in favour of or against one group of people, or one side in an argument, often not based on fair judgement
to have an effect on the results of research or an experiment so that they do not show the real situation
Definitions: oxfordlearnersdictionaries.com/us/definition/english/bias_2 / oxfordlearnersdictionaries.com/us/definition/english/bias_1
Your research question should be open and unbiased. If your question is too biased you may only find results that support your initial hypothesis and miss other, critical information.
This question assumes that social media sites are inherently harmful. It can be rephrased to focus on a specific perceived harm, such as the impact of social media sites on self-esteem.
This question is more specific, and focuses on finding evidence about effect or impact, rather than harm. This search may return results that show a harmful impact or research that shows a beneficial impact.
The words we use can have many meanings. Some words are emotionally charged or have specific, biased connotations. Words may fall in and out of usage over time. It is important to try to use neutral, academic terms that are current. Adolescent will return more academic sources than kid; developmentally delayed will return more recent results than an outdated (and now offensive) term like retarded.
The term illegal aliens is politically and emotionally charged. Recent research has favored other terms, so using this search is more likely to return either out-of-date results or biased sources.
This question uses a more current, neutral term to ask the same question.