Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve phan » va phan, ke phan, ve phat
va hanh » van hanh, va danh, ban hanh
vi su » ve su, ki su, oi su

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ty nang xa hoi. hieu ve phan tu ((va hanh) or (va thanh)) ((vi su) OR (va su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ty nang xa hoi. hieu ve phan tu ((va hanh) OR (va thanh)) ((vi su) OR (va su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty nang xa hoi. hieu ve phan tu ((va hanh) or (va thanh)) ((vi su) OR (va su)) triet".
• Adding a wildcard symbol may retrieve word variants: so sach ty nang xa hoi. hieu ve phan tu ((va hanh) or (va thanh)) ((vi su) OR (va su)) triet*.