Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hang vai » hang tai, hang hai, hang vi
su sach » so sach, vu sach
van cac » van hac, van cau, van bac
cua tre » cuu tre, cua triet, dua tren
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
du ban » dua ban, duc ban, du bao
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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 van cac du ban ((hang vai) or (hang va)) ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang o hoi. hieu van cac du ban ((hang vai) OR (hang va)) ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang o hoi. hieu van cac du ban ((hang vai) or (hang va)) ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: su sach y nang o hoi. hieu van cac du ban ((hang vai) or (hang va)) ((cua tre) OR (cua te))*.