Boolean Operators and Advanced Search Techniques

Not every task needs advanced techniques. But they’re worth using when:

• You get too many irrelevant results

• You can’t find enough sources

• You’re searching in a large or complex database

• You need to show a structured, repeatable search strategy

• You’re doing a dissertation, literature review, or PGR-level work

Boolean operators are special words (AND, OR, NOT) that help you control how search tools combine your keywords.

• AND – narrows results by combining different ideas (e.g. anxiety AND sleep)

• OR – broadens results by including synonyms (e.g. teenager OR adolescent)

• NOT – excludes results with specific terms (e.g. stress NOT workplace)

Tip: Always use uppercase (AND, OR, NOT) — many search tools expect it.

Use double quotation marks to search for an exact phrase.

Examples:

• "climate change"

• "data protection"

• "corporate social responsibility"

Without quotation marks, the search tool may treat the words separately.

Tip: Use phrase searching to make your results more precise.

Use brackets to group terms and control the logic of your search.

Example:

• (anxiety OR stress) AND sleep

This tells the database to find sources that mention either anxiety or stress — but also include sleep.

Without brackets, your search may run in the wrong order.

Tip: Brackets help especially when combining OR with AND.

Psychology
(anxiety OR depression) AND "young adults"

Business
("corporate social responsibility" OR CSR) AND marketing

Computing
AI AND ethics AND (bias OR fairness)

Health Sciences
("patient safety" OR "clinical risk") AND hospitals

Law
("human rights" OR "civil liberties") AND surveillance

Truncation helps you find all forms of a word by adding an asterisk *.

Examples:

• educat* → education, educating, educator

• comput* → computer, computing, computational

Wildcards let you replace a single character (varies by database):

• wom?n → woman, women

• colo?r → color, colour

Tip: These work in many databases, but not all — check the help page for the tool you’re using.

Some databases let you control how close words appear to each other.

Examples:

• "climate NEAR/3 crisis" → finds "climate crisis" or "crisis in climate policy"

• "leadership W/5 innovation" → finds results where the words are within five words of each other

Tip: Different databases use different syntax. Try NEAR/n, W/n, or N/n depending on the platform.

Too many results?

• Add more keywords

• Use AND to narrow your search

• Use quotation marks for phrases

• Apply filters (e.g. peer-reviewed, date range)

Too few results?

• Use OR for synonyms

• Try truncation or wildcards

• Remove overly specific terms

• Use fewer filters

Not relevant?

• Rethink your keywords

• Try broader or more precise terms

• Use brackets to combine ideas better

Use this basic template to construct your own advanced search:

("first keyword" OR synonym) AND ("second keyword" OR synonym)

Examples:

• (stress OR anxiety) AND (university OR "higher education")

• (ethics OR fairness) AND AI AND hiring

Tip: Keep a copy of your search strings — you’ll need them for your dissertation or literature review.

Tracking your searches helps you avoid repeating work — and shows your search was systematic.

Note: You don’t usually need a full search log for standard UG assignments. But it’s a good habit to start — and essential for dissertations, literature reviews, or PGR research where you must show how you searched.

A search log helps you:

• Reflect on what’s working (and what isn’t)
• Save useful searches for future use
• Demonstrate your academic rigour
• Support the “methodology” or “search strategy” sections in your assignment or thesis

Example – Search Log Format

Tip: You don’t have to use this exact format — any consistent way of recording your searches will help, especially for dissertations or PGR work.

Each platform behaves slightly differently. Always check the database’s Help or Search Tips section.

Examples:

• Scopus supports truncation, wildcards, phrase searching, proximity, and field searching

• Web of Science allows precise control over fields and citations

• CINAHL uses a different syntax for proximity (N3 instead of NEAR/3)

• Google Scholar allows phrase searching but not Boolean brackets or proximity

Tip: A good search in one tool might need adjusting in another.

AI tools can help spark ideas — but they can’t search academic databases for you.

ChatGPT, Copilot, and similar tools:

• Can suggest keywords or synonyms

• Might explain Boolean logic or search tips

• Do not access peer-reviewed journals or library databases

• May hallucinate sources or give incorrect search syntax

AI is also changing how we search. Some platforms now let you use natural language queries or offer AI-generated summaries — but:

• Most academic databases still rely on Boolean operators and structured search

• Boolean logic gives you precise control, especially for high-level research

• Structured searching is transparent and repeatable — important for dissertations, literature reviews, and PGR work

Tip: Use AI to support your thinking — but rely on academic tools for structured, reliable searching.