PDF Search Answers
Last reviewed: September 1, 2026 · Markdown version
One honest answer per problem — including the limits no app escapes.
How to search for a word in a PDF
Start here. The find function every reader has, and the three reasons it comes up empty on a word you can see on the page.
How to search inside many PDFs at once
Most PDF apps search one open file. What that means on a phone, the manual workaround, and when an index across the whole library is the honest answer.
How to search inside PDFs on iPhone
Two questions in one: searching the file you have open, and searching everything you've saved. What each route does, and where the second one needs an index.
How to search inside PDFs on Android
The same two routes, Android-side — plus the script limit nobody mentions: which scanned pages can be made searchable and which can't.
PDF search not finding words that are clearly there?
The three causes, in order of likelihood — a scanned page, OCR errors, or text that isn't stored as text — and the ten-second test that tells you which one you have.
How to make a scanned PDF searchable
A scan is a photograph, so OCR is the fix — and the decision that matters is whether the recognition runs on your own device or on someone else's server.
Can you search inside a password-protected PDF?
PDF has two kinds of password and they behave completely differently — one blocks everything, the other does not block search at all. Which is which, and what DocFind does with each.
Does OCR work on handwritten notes?
The honest answer for DocFind is no, and it is worth knowing why — plus what printed scans do get, and the script limit that applies to scanned pages on Android.
How do I search PDFs without uploading them?
Indexing and OCR run on the device, the index stays there, and the iPhone app ships with no network capability at all — which is a property you can check rather than a promise you have to trust.
What is OCR, and why do scanned PDFs need it?
OCR turns a picture of text into text a computer can search. How it works, where it runs (on your device or on someone's server — a privacy question), and what it honestly can't read.
Have a question these don't answer? Tell us — the honest version of the answer is the page we'll write next.