Perhaps you should try some spelling variations:
van thanh » ban thanh
qua pham » quan pham, quy pham, qua cham
van tuan » van quan, van ban, anh tuan
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cua tre » cuu tre, cua triet, dua tren
nang o » nang co, nang ho, nang ro
cua te » cua tu
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: su sach ky nang o hoi. hieu qua pham duc ((van thanh) OR (van tuan)) ha ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang o hoi. hieu qua pham duc ((van thanh) OR (van tuan)) ha ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang o hoi. hieu qua pham duc ((van thanh) OR (van tuan)) ha ((cua tre) or (cua te))*".