Perhaps you should try some spelling variations:
phan tien » phan kien, phan bien, phap tieng
thu sach » tu sach, thuat sach, thuoc sach
cao suc » cao su, cao duc
hieu ve » hieu van
va phan » van phan, va phat, va phap
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
suc va » duc va, tuc va, luc va
nang o » nang co, nang ho, nang ro
cua tu » cua tuc, cua su, cua cu
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: thu sach ky nang o hoi. ((hieu ve) OR (hieu va)) cao suc va phan tien ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang o hoi. ((hieu ve) OR (hieu va)) cao suc va phan tien ((cua te) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang o hoi. ((hieu ve) OR (hieu va)) cao suc va phan tien ((cua te) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang o hoi. ((hieu ve) OR (hieu va)) cao suc va phan tien ((cua te) or (cua tu))*.