Pennsylvania-eighteenth century-Philadelphia to Lancaster

i'm still working on this whole emigrant thing....and once again i'm at a loss for information.....

i've been working on this story about someone who has come from germany in 1738 to philadelphia.....and did not show up in the census records again until 1761...according to ship records he was 23 at the time he arrived in philadelphia....i'm trying to figure out where he could have been for those 23 yrs where there is no mention of him.

i realize he could have been an indentured servant....but for 23yrs.....that was only a seven yr contract or 14yr in some cases right?

i welcome any resources you might have....i have no problem researching....as long as i know where and how to research it.

thanks a bunch for your info....and thank you to those who have helped me prior to this new thread....all your information has been helpful!!

C