I'll start again,

Lets say My data is:

Table element (id,name,....)

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1, name element 1, ....

2, name element 2, ....

3, name element 3, ....

Table tags (id,name,id_element, ....)

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1, happy , 1

2, result, 1

3, very , 1

4, element, 2

5, another, 3

6, element, 1

7, happy, 2

So if search is 'very, happy,element,result': Results i would like

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1) element with id = 2 because it has all tags

2) element with id = 1 because it has the tag 'element' and the tag 'happy' (only 2 less taggs)

3) .... (only 3 less taggs)

So if search is 'happy,element': Results i would like

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1) element with id = 1 because it has all tags (and no more)

2) element with id = 2 because it has the tag 'element' and the tag 'happy' (and two more tags)

3) .... and 3 more tags

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This is an echo to my query: (it doesn't fit al requirements i wrote, but its first test to find with matched tags)

SELECT element.id as id_deseada,tagg.* FROM element,tagg WHERE tagg.id_element = element.id AND tagg.nombre IN ('happy','tagg','result') GROUP BY tagg.id_element ORDER BY element.votos 

This returns 10 duplicated elements... :S and doen't even have all taggs (and on database there are taggs with 'happy' results)

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if it helps, thats how i get the elements of a tag (by name and with only one tagg)

$query = "SELECT element.id FROM element,tagg WHERE tagg.nombre = '$nombre_tagg' AND tagg.id_element = element.id  AND lan = '$lan' GROUP BY tagg.id_element";

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I hope it's a bit easier to understand now, excuse my english.. :)

Thanks a lot for you possible aportation!