Perhaps you should try some spelling variations:
sach thi » sach tai, sach thieu, sach tham
sach thu » sach thue, sach thieu, sach tham
thuc day » thuc dan, thuc vat
day hanh » day nhanh, day thanh, dao hanh
hanh xa » hanh va, hanh ma, hanh xu
hieu ve » hieu va, hieu van
vai cua » hai cua, lai cua, bai cua
ve am » va am

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thi) or (sach thu)) hanh xa hoi. hieu ve am thuc day hanh ((vai cua) OR (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thi) OR (sach thu)) hanh xa hoi. hieu ve am thuc day hanh ((vai cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach thi) or (sach thu)) hanh xa hoi. hieu ve am thuc day hanh ((vai cua) OR (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach thi) or (sach thu)) hanh xa hoi. hieu ve am thuc day hanh ((vai cua) OR (dai cua)) triet*.