Perhaps you should try some spelling variations:
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
hanh di » hanh vi, hanh de, danh di
hang di » hang doi, hang vi, hang dien
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai
ve am » va am
thuc » thu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang o hoi. hieu ve am thuc vat ((hanh di) or (hang di)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang o hoi. hieu ve am thuc vat ((hanh di) OR (hang di)) cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach y nang o hoi. hieu ve am thuc vat ((hanh di) or (hang di)) cuu tre*.