Perhaps you should try some spelling variations:
pham chuc » pham duc, pham huu, kham chua
thu nang » thi nang, thu hang, thu bang
nang mai » nang ma, nang tai, lang mai
hanh hai » thanh hai, nhanh hai, hang hai
hieu van » hieu va, thien van, lieu va
so sach » bo sach, co sach, hoc sach
chuc va » thuc va, thuc vat
hai cua » thai cua, dai cua, hoi cua
so sanh » do sanh
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va
va hanh » van hanh, va thanh, va danh
cua te » cua tu

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)) thu nang mai hoi. ((hieu ve) OR (hieu van)) pham chuc va hanh hai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) thu nang mai hoi. ((hieu ve) OR (hieu van)) pham chuc va hanh hai cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (so sanh)) thu nang mai hoi. ((hieu ve) OR (hieu van)) pham chuc va hanh hai cua te*".