When the Patient Has Vague Symptoms, Ask the Right Questions

https://www.sciencedirect.com/science/article/abs/pii/S1555415519302193

See also 

https://www.jabfm.org/content/jabfp/7/1/86.full.pdf

https://www.topdoctors.co.uk/medical-articles/deciphering-vague-symptoms-when-to-see-an-internal-medicine-specialist

https://geri-em.com/atypical-presentations/vague-or-multiple-complaints/

https://www.buckshealthcare.nhs.uk/wp-content/uploads/2021/05/Vague-symptoms-pathway.pdf

https://www.annemergmed.com/article/S0196-0644(21)01203-8/fulltext