Perhaps you should try some spelling variations:
phan duc » pham duc, phan tu, phan dau
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
hieu ke » hieu kem, chieu ke, hieu ky
ke phan » ve phan, kenh phan, ke thang
sach ty » sach y, sach tu, sach thu
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
ma hoi » mai hoi, xa hoi, ma hoa
oi su » ki su, vi 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 ty nang ma hoi. hieu ke phan duc va hanh ((((oi su) or (va su))) or (ve su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ma hoi. hieu ke phan duc va hanh ((((oi su) OR (va su))) OR (ve su)) triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ma hoi. hieu ke phan duc va hanh ((((oi su) or (va su))) or (ve su)) triet*.