We recently updated a Magento install from 22.214.171.124 to 126.96.36.199. Everything worked fine, expect the search function. Whatever we searched for, the site returned just one result. This seems to be a problem with upgrades and even some fresh installs of Magneto 188.8.131.52, 1.4.2, 184.108.40.206, etc. The following is the fix. This will require fixing the core files. Hopefully the Magento team will address the issue in the next update.
Uncomment lines 149 and 150
Modify the line 172
// Change this line $this->_productCollection = $this->getListBlock()->getLoadedProductCollection();
to the old code from Version 220.127.116.11
// Change the previous line to this one $this->_productCollection = Mage::getSingleton('catalogsearch/layer')->getProductCollection();
Once the code is fixed, go to the Admin panel (System > Index Management) and select all the Indexes > Pick action is “Reindex data” > Press “Submit”.
The search should work now.