Perhaps you should try some spelling variations:
pham chuc » pham duc, pham huu, kham chua
pham cuc » pham duc, pham cua, pham thuc
ban hanh » ban hang
hanh dai » hanh tai, hanh dao, vanh dai
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
o hoi » co hoi, o hai, o hoa
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu cac ky nang ((o hoi) or (o hoc)). hieu va ((pham cuc) OR (pham chuc)) ban hanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cac ky nang ((o hoi) OR (o hoc)). hieu va ((pham cuc) OR (pham chuc)) ban hanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cac ky nang ((o hoi) or (o hoc)). hieu va ((pham cuc) OR (pham chuc)) ban hanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu cac ky nang ((o hoi) or (o hoc)). hieu va ((pham cuc) OR (pham chuc)) ban hanh dai cua tre*.