I am trying to figure out how to make a Mysql Select with an OR in where Clause. By default all clauses in where statement are ANDed and after some hours of try and fail and
There is no orWhere in ZF2, but you could use any combination of Zend\Db\Sql\Predicate objects. For OR use 2 predicates in a PredicateSet with PredicateSet::COMBINED_BY_OR.
There's not much documentation for it, but you could browse the source - for now.
Edit: sample
use Zend\Db\Sql\Predicate;
$select->where(array(
    // ...
    new Predicate\PredicateSet(
        array(
            new Predicate\Like('content', '%'.$searchstring.'%'),
            new Predicate\Like('title', '%'.$searchstring.'%'),
        ),
        Predicate\PredicateSet::COMBINED_BY_OR
    ),
    // ...
));
                                                                        or you cloud use:
$select->where
    ->like('content','%'.$searchstring.'%')
    ->or
    ->like('title','%'.$searchstring.'%');