Answer
Apart from any other browser you search on, there are a number of search engines that are especially designed for the purpose of academic research. They can help you get your hands on relevant information without going through irrelevant or low-quality pages.
Search engines allow researchers to enter search terms.
1. This sentence can mean two things:
1) A child-teaching expert is going to speak.
2) A child is teaching an expert how to speak.
2. This sentence can mean two things:
1) Dogs have faith in the Rehoming Center.
2) The name of the institution - "Dogs Trust Rehoming Center"
3. This sentence can mean two things:
1) Smoking rooms aren't available
2) Rooms in which there is no smoking are available
4. This sentence can mean two things:
1) Anadin is the fastest working medicine
2) Taking nothing instead of Anadin is the better choice
All of these sentences are ambiguous, meaning that they have at least two opposing meanings.
A thesaurus maybe, to find the synonyms of convenient.