A well-defined query makes it easier for you to find relevant literature.
Start by identifying the keywords in your search query i.e. by extracting the significant terms.
(Can resistance training reduce pelvic pain in pregnant women?)
Then find words that describe these terms.
Since most literature is published in English your search words should also be in English.
Your terms will then form a search block.
Synonyms and similar words are combined with OR to a "block".
The blocks are then combined with AND.
If it can be applied to your research question, different search strategies may be of help in structuring your search. One of the most well-known search strategies is PICO, which stands for:
Each “letter” in PICO forms a search block. All the “letters" do not always have to be included in the search. The usual case is that a search consists of only "P" and "I" for example.
There are also other models, e.g. SPIDER and SPICE below.
Statens lantbruksuniversitet. (2019) Research question and selection criteria. Retrieved 2019-12-18 from https://slu-se.instructure.com/courses/167/pages/research-question-and-selection-criteria (CC BY-NC-SA 4.0)