Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hang loi » thang loi, hang doi, tang loi
pham duy » pham duc
hieu va » lieu va
sach tu » sach thu, cach tu, sach ty
hanh de » hanh ve, hanh kem
tu nang » tru nang, tu nong, tu nano
vu sach » vu bach, su sach, vu khach
duy va » duy vat, duy van, day va
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach tu nang x hoi. ((hieu va) OR (hieu qua)) pham duy va ((hanh de) or (hang loi)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach tu nang x hoi. ((hieu va) OR (hieu qua)) pham duy va ((hanh de) OR (hang loi)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach tu nang x hoi. ((hieu va) OR (hieu qua)) pham duy va ((hanh de) or (hang loi)) cua triet".
• Adding a wildcard symbol may retrieve word variants: vu sach tu nang x hoi. ((hieu va) OR (hieu qua)) pham duy va ((hanh de) or (hang loi)) cua triet*.