Perhaps you should try some spelling variations:
phan duc » pham duc, phan tu, phan dau
tu sach » thu sach, su sach, te sach
bo sach » co sach, hoc sach
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
hieu vi » hieu voi, hieu va, hieu ve
vi phan » va phan, vi pham, ve phan
va dan » ca dan, va dao, va dau
dan de » dan den, dang de, van de
de cua » le cua, te cua, dieu cua
cua su » qua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (bo sach)) ky dang xa hoi. hieu vi phan duc va dan de cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (bo sach)) ky dang xa hoi. hieu vi phan duc va dan de cua su.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (bo sach)) ky dang xa hoi. hieu vi phan duc va dan de cua su*.