Here are two resources/methods that can help a researcher identify relevant synonyms:
Thesaurus: A thesaurus is a reference work that lists words grouped together according to similarity of meaning. Using a thesaurus can help a researcher identify synonyms that are relevant to their research topic. Online thesauruses like Thesaurus.com or Merriam-Webster's Thesaurus can be helpful in identifying synonyms.
Brainstorming with peers or experts: Brainstorming with peers or experts in the field can also help a researcher identify relevant synonyms. By discussing the topic with others, the researcher may gain new perspectives and insights that can help identify relevant synonyms. Additionally, brainstorming with others may lead to the discovery of new words or phrases that are relevant to the topic.