Uniformize, and more, the keywords /.../ in the search of the catalogue

The help article https://en.numista.com/help/how-can-i-search-the-catalogue-99.html has different keywords for special search in the catalogue, and these are different by language:

EN

/new7/
/no-picture/
/small-pictures/
/missing-unabridged/
/unverified/
/incomplete/

FR

/nouveau7/
/sans-photos/
/petites-photos/
/manque-non-abrégée/
/non vérifié/
/incomplet/

ES

/nuevo7/
/sin-imagen/
/imagenes-pequeñas/
/falta-sin-abreviar/
/no-verificada/
/incompleta/

I see problems and inconsistence:

• Use spaces or hyphens. EN/FR/ES use hyphens except FR /non vérifié/
• Use accents or not. It is not problem in EN (there are not accents), but FR/ES/others have accents. Now keywords FR use accents and ES use not.

This must be uniform in all languages:

• always spaces (more natural language for users) or always hyphens;
• always with accents (more natural language for users) or always without accents.

With more languages, more could appear.

My suggestion:

1. Uniformize all languages: use natural language (spaces and accents)

These keywords has the character “/” at beginning and at ending, so I think can be used the natural language in all (spaces and accents). For example:

• EN /missing-unabridged/ → /missing unabridged/
• FR /manque-non-abrégée/ → /manque non abrégée/
• ES /imagenes-pequeñas/ → /imágenes pequeñas/

2. Recognize keywords with hyphens, without accents, or with uppercase

But I think if an user write a keyword with hyphens or without accents (or with uppercase!), the system should recognize the keyword. Por example:
 

1. The user write:
   INPUT = /Manque-non-abregée/
2. The system detect a keyword (/…/) and replace hyphens by spaces, remove accents and write all in lower case:
   EDITED INPUT = /manque non abregee/
3. The system searches for this keyword among those stored in the interfaz language:
   • For each keyword stored, remove accents and compare with edited input.

3. Recognize keywords in the other supported languages

By other hand, users can use the interface in their language and in English (for example), and write the keyword in the other language by mistake (or change the language in a search results, this case is supported now). Because of this, the system should recognize the keyword in a different language of the interface language. Por example:

1. The user has English interface, but write in French:
   INPUT = /Manque-non-abregée/
2. The system detect a keyword (/…/) and replace hyphens by spaces, remove accents and write all in lower case:
   EDITED INPUT = /manque non abregee/
3. The system searches for this keyword among those stored in the interfaz language:
   • For each keyword stored, remove accents and compare with edited input.
4. If it is not found, the system searches for this keyword among those stored in the other supported languages:
   • For each keyword stored, remove accents and compare with edited input.

NOTE: The process “remove accents from the stored keyword” can be avoided if the system save two versions of each keyword:

• with accents, displayed to the user; and
• without accents, used in comparisons by the system.

This other suggestion goes a step further: https://en.numista.com/forum/topic153413.html