To successfully search for information on your topic, it is best to determine the main concepts and then find keywords for those concepts. The keywords can become your search words. In general, you should search library databases approximately 3 keywords, rather than your whole topic question or a sentence.
For example, your research question is Will climate change cause flooding in cities around the world?
Mark the keywords (italics in this example).
Then begin generating synonyms and related words to help you develop a search strategy.
||sea level rise
In many databases, you could start your search by typing climate change cities flooding and it would automatically turn that search into:
climate AND change AND cities AND flooding
This is a search using Boolean logic.
A more advanced Boolean search could be done like this:
("climat* change*" OR "global warming") AND (city OR cities OR urban) AND flood*
In this example the * will also find different endings for the words, such as climate or climatic, flood, floods or flooding.
Here are some more tips for choosing keywords.
You can also find additional keywords by searching your topic in a database, finding a relevant item and noting the terms used in the description of that item.