When you are accessing Blockchain.info, make sure that you are entering your transaction hash correctly in the search box. If your transaction ID appears in URL like this: https://blockchain.info/tx/9593513fc20fe356c7eca3e152f8722de3a0128c805466af05caa05237564f5a then you only need to copy your hashing number which is 9593513fc20fe356c7eca3e152f8722de3a0128c805466af05caa05237564f5a and paste it on the search box.
Sometimes there are also different factors such as a problem in Blockchain.info’s server or the transaction has not reached the Blockchain.info node. If this occurs, please use another block explorer site such as:
Copy your transaction hash (only the hashing number, not the entire URL) on the search box provided by those block explorers. You may also search your transaction by pasting down your Bitcoin address.