My mum has been throwing up everyday for the past 5 years, now she throws up blood

Your mum really needs to go back to the doctor because she will get malnourished with all the vomiting and the bleeding needs to be investigated.  Has your mother tried a food diary to pinpoint a food problem?  The diet changes she has made may not be working because the foods she has eliminated may not be problem foods.   With a food diary you record what you ate, the time you ate it and any reactions you get.  It sounds as if her stomach is trying to get rid of an irritant.  Migraines often make people vomit and certain foods may also cause them.  The medications she takes could also be the cause too.  Check the side effects online or on the patient leaflet to see if they cause nausea and vomiting.

I would think she has a deficiency.. Vitamin D, Magnesium, Calcium, Iodine, iron etc.. plus she probably is low on sodium -  since she is throwing up so much. 

I would recommene taking a multivitamin + extra magnesium an calcium and drinking much more water with added mineral drops. 

Has she had a certain normal brain scan, but for question of Chiari?

Not every radiologist looks for that. Result definitely has to state something about 'Chiari', otherwise it was not looked at.

Has she had a vascular brain scan, too?

Has she been checked for MALS or nutcracker or SMAS?

Ultrasound is the best check for it

(mesenteric artery scan, she has to lie down and exhale for MALS. Otherwise done incorrectly.

Nutcracker is compression of left renal vein and can be seen in ultrasound of left renal vein or in MRA, CTA. If radiologist was not asked to look for it, it often goes unnoted.

SMAS/Wilkie lies within the same compression as the left renal vein, but the duodenum itself is compressed)

These are often not known reasons for vomiting and migraines and often not easy to fix, but often a relief to know about it as one worries sick what was happening and the 'psychological' labelling just not satisfying.

My daughter has MALS, nutcracker and mild SMAS,

her migraines are due to this or her poor neck posture (is hypermobile) it seems and very often. (another attack just right now)

She vomits every day, also traces of blood sometimes = this is, when she has to go on liquid diet and PPI.

Scratching throat can be the acid irritating the oesophagus

simply as a second impact by vomiting acid up all the time.

My daughter takes H2 blockers, they are not as strong as PPI, when she is only vomiting not too badly after food or when lying down without blood.

My girl's migraines can only be helped by taking a medication of the -triptan family.

No over the counter painkiller helps, no antihistamin, no peppermint oil, no cold wash cloth.

So she can't take it often.

For vomiting and nausea she takes ondansetrone.

We have to do liquid diet often, make smoothies, eat soups, gastroparesis diet (low fibre).

Your mother could also do a gastric emptying study. It does not say as to why the stomach was emptying too slowly, but shows if it was too slow. If vomiting was a problem to investigate that path.

Best of luck

and hopefully she can go with very precise questions to doc,

maybe join specific fb groups according to the disease names I mentioned as often docs don't know about rare reasons for migraines or vomiting. Those groups have files or can be asked about doctors in the same living area, which ones to go to to not waste more time and money.

Exclusion is also peace of mind.

All all the best