Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
can thuc » dan thuc, van thuc, san thuc
lang van » dang van, tang van, hoang van
cay thuc » cay thuoc, day thuc, cach thuc
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
van hoe » van hoa, van hoc, van hieu
va lang » va nang, hoa lang
so sanh » do sanh
cua tuc » cua duc, cua tu, cua thuoc
di cua » dai cua, doi cua, de cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (so sanh)) va lang van hoe. hieu qua ((cay thuc) or (can thuc)) va hanh di cua tuc~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (so sanh)) va lang van hoe. hieu qua ((cay thuc) OR (can thuc)) va hanh di cua tuc.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (so sanh)) va lang van hoe. hieu qua ((cay thuc) or (can thuc)) va hanh di cua tuc*.