Perhaps you should try some spelling variations:
sach thuc » cach thuc, sach thu, sach thue
manh hanh » xanh hanh, danh thanh, minh thanh
duc manh » suc manh, duc anh, duc minh
vu sach » vu bach, su sach, vu khach
hanh va » hang va, hanh vi
van cam » van nam, van lam, van dam
van cau » van dau, van hau, van chat
lai cua » hai cua, lai chau, thai cua
va hoi » xa hoi, va hoc, va hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach thuc hanh va hoi. hieu ((van cam) or (van cau)) duc manh hanh ((lai cua) or (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach thuc hanh va hoi. hieu ((van cam) OR (van cau)) duc manh hanh ((lai cua) OR (dai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: vu sach thuc hanh va hoi. hieu ((van cam) or (van cau)) duc manh hanh ((lai cua) or (dai cua)) tre*.