(If your research story looks like this, do not fear!)
Advanced Search is your friend. Specificity and knowing what you're looking for will help you focus on the most relevant sources.
Synonyms help you find more/new resources. Keep an eye out for the types of language that researchers are using and know that it may change over time.
"Quotation Marks" can be used around phrases to search for the entire phrase together. "Internet addiction" "single parents"
* signifies truncation. A title search for "teen*" will include results with the words teen, teens, teenagers, teenager, teenage
Cited References may help you find relevant, more recent research.
PsychNET is an amazing resource for Psychology students, but it is not the only one. Here are a few other resource you may want to explore, especially as you work throughout the semester.