Pesquisa vs. investigação
While both words can translate to "research" or "investigation" in English, their usage distinction often depends on the region (Brazil vs. Portugal) and the nature of the activity. Generally, pesquisa implies gathering data or searching for information, while investigação implies aggressive scrutiny, solving a mystery, or police work, though regional differences apply.
Pesquisa
B1This word refers to a systematic search for information, data collection, or academic study. In Brazilian Portuguese, it is the standard term for scientific research. It is also used for simpler contexts like internet searches or opinion polls.
A pesquisa de mercado indicou que os clientes querem preços mais baixos.
(The market research indicated that customers want lower prices.)
Eu fiz uma pesquisa rápida no Google para encontrar o endereço.
(I did a quick search on Google to find the address.)
Os cientistas publicaram uma nova pesquisa sobre a cura do câncer.
(The scientists published new research on the cure for cancer.)
Minha filha está fazendo uma pesquisa escolar sobre o ciclo da água.
(My daughter is doing school research about the water cycle.)
A última pesquisa eleitoral mostra os dois candidatos empatados.
(The latest electoral poll shows the two candidates tied.)
Investigação
B2This implies a deep examination to uncover hidden truths, heavily associated with detective work, journalism, or police inquiries. However, in European Portuguese (Portugal), this is also the formal and primary word for scientific or academic research, where a Brazilian would typically use pesquisa.
A polícia abriu uma investigação para descobrir quem roubou o banco.
(The police opened an investigation to find out who robbed the bank.)
O jornalismo de investigação expôs a corrupção no governo.
(Investigative journalism exposed corruption in the government.)
O detetive particular continua sua investigação sobre o desaparecimento.
(The private investigator continues his inquiry into the disappearance.)
O centro de investigação da Universidade de Lisboa recebeu um prêmio.
(The University of Lisbon's research center received an award.)
Houve uma investigação interna na empresa para apurar as falhas de segurança.
(There was an internal investigation in the company to determine the security flaws.)
Summary
Use pesquisa when you are talking about searching for data, Googling something, taking a poll, or doing academic work in Brazil. Use investigação when discussing crimes, police work, or uncovering secrets. Remember that in Portugal, investigação is often used for scientific contexts where a Brazilian would say pesquisa.