About Search Entries:
Every time a lender checks your credit history from your credit file (i.e. each time you apply for a loan), your credit-file will have a record of this. These records are known as search entries. The search entries do not generally say whether you were approved or denied credit, but they do reveal the name of the lender(s) processing previous applications. Lenders automatically impart this information back the credit bureaus and see it as an important tool.
As you can imagine, with this information other lenders can see if you have been applying for many, many loans. The lender dealing with your current application would expect to see a few search entries, but if there are more than, say, 20 in a few months he will be very wary, and may reject your application. (Of course he will be adding one more entry to your credit-file himself in the process!).The original reason for a credit search entry being inserted into credit files was to check for fraud, but lenders have since found much value in watching the habits of consumers applying for credit.
There is no specific number of searches that would cause an application to be turned down flat, but as above, too many unrelated credit searches on your credit file will certainly not be helpful in your quest to get approved for credit.
Limiting credit search entries:
Try to limit search entries by only applying for 1 or 2 loans a month. If you see duplicate searches appearing on your credit file for the same loan, these should be removed. Write to the credit agencies to ensure they are. All searches should expire after 2 years, so check that they are deleted after this time and if not you can insist this is done too.
Once your credit file contains a minimal number of credit search entries then you can be sure that you have the best chance for getting approved for your next loan.