The local-osm-search plugin uses the method:
QString OsmDatabase::wildcardQuery( const QString &term ) const

in order to inglobe the searched place in the query
The problem is that the returned QString uses the single apex and if the QString term already contains an apex the returned value will be wrong because will be interrupted at the first apex of the term.

Reproducible: Always

Steps to Reproduce:
1. Insert an address containing an apex (like: Via Sant'Orsola, Milano).
2. Try to search it and wait the result.
3. Check the result.
Actual Results:  
The results are wrong because marble will search for: "Via Sant, Milano"

Expected Results:  
The software should search for "Via Sant'Orsola, Milano"

the following block:
    if ( term.contains( '*' ) ) {
        return " LIKE '" + result.replace( '*', '%' ) + '\'';
    } else {
        return " = '" + result + '\'';
    }

should be like this:
    if ( term.contains( '*' ) ) {
        return " LIKE \"" + result.replace( '*', '%' ) + "\" ";
    } else {
        return " = \"" + result + "\"";
    }