Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve chao » ve chat, ve cham, ve cho
y nang » ky nang, ly nang, v nang
xu van » tu van, vu van, su van
lam va » nam va, lam ha, cam va
dam va » dam van, nam va, dam ha
am va » nam va, cam va, am vi
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: su sach y nang xa hoi. hieu ve chao xu van hanh ((((lam va) or (am va))) or (dam va)) thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang xa hoi. hieu ve chao xu van hanh ((((lam va) OR (am va))) OR (dam va)) thiet.
• Adding a wildcard symbol may retrieve word variants: su sach y nang xa hoi. hieu ve chao xu van hanh ((((lam va) or (am va))) or (dam va)) thiet*.