If your Thai girlfriend is planning on traveling to the UK and then having a holiday in Spain france or Tenerife they will need two visas. The first visa will be the UK tourist visa, but your Thai girlfriend will not be able to travel from the UK into Spain France Tenerife on a UK Tourist visa. Even though the UK is part of Europe, different visas will be required to allow your Thai girlfriend to travel into each member state within Europe.
Plan Thai girlfriend travelling to Spain and France.
If your girlfriend is travelling to the UK on a tourist visa, then she will not be able to apply for a visa to Spain, France Tenerife in the UK, the visa to travel to these areas needs to be arranged in Bangkok before she travels to Europe.
Thai girlfriend will not be able to travel from the UK into Spain France Tenerife on a UK Tourist visa
Schengen visa is required for a Thai citizen
The Visa that she will require is the Schengen visa. The Schengen visa is required for a Thai citizen to travel to Austria, Belgium, Denmark, France, Finland, Germany, Greece, Italy, Luxemburg, The Netherlands, Norway, Portugal, Spain, and Sweden.
Please note a Schengen visa to Spain will not allow entrance into France, your Thai girlfriend would need a separate visa for each of the countries listed above.