Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
cham duc » pham duc, cham soc, phan duc
pham duy » pham duc
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, sach thu
vu va » vu van, tu va
su va » su van, tu va
thiet » thieu

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 xa hoi. hieu ve ((cham duc) or (pham duy)) van hanh ((vu va) OR (su va)) thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang xa hoi. hieu ve ((cham duc) OR (pham duy)) van hanh ((vu va) OR (su va)) thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. hieu ve ((cham duc) or (pham duy)) van hanh ((vu va) OR (su va)) thiet".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. hieu ve ((cham duc) or (pham duy)) van hanh ((vu va) OR (su va)) thiet*.