Perhaps you should try some spelling variations:
pham chuc » pham duc, pham huu, kham chua
thi nang » thi cong, ki nang, thi hanh
so sach » bo sach, co sach, hoc sach
va pham » van pham, va phat, va phap
tai cua » thai cua, tai cuc, tri cua
so sanh » do sanh
van tai » von tai, van tuan
chuc va » thuc va, thuc vat
hieu va » lieu va, hieu qua
co hoi » co hoc
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (so sanh)) thi nang ((co hoi) OR (co loi)). hieu va pham chuc va van tai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) thi nang ((co hoi) OR (co loi)). hieu va pham chuc va van tai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (so sanh)) thi nang ((co hoi) OR (co loi)). hieu va pham chuc va van tai cua tu".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (so sanh)) thi nang ((co hoi) OR (co loi)). hieu va pham chuc va van tai cua tu*.