While there's nothing inherently wrong with the virtual QWERTY keyboard on iOS devices, making mistakes while typing is inevitable. Accidently place your finger on an alphabet you don't want to enter and the touchscreen registers it as a tap, which results in a typo. The App Store's search engine used to be very specific, making a spelling mistake when searching for an app's would result in that app not being displayed in the search results. TechCrunch claims to have learnt that Apple tweaked the search engine a few weeks ago and it now disregards misspelled queries. This obviously results into better search results.
Ubergizmo , Apple Tweaks App Store Search Engine To Disregard Spelling Mistakes, Apple Tweaks App Store Search Engine To Disregard Spelling Mistakes