Perhaps you should try some spelling variations:
van thiet » va thiet, dan thiet, can thiet
va thanh » gia thanh, ban thanh, va tinh
van hanh » van thanh, ban hanh, van anh
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cac xuc » cam xuc, cac nuoc, chat xuc
x hoi » xa hoi, o hoi, x ho
nuoc » quoc, duoc, ngoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ty nang x hoi. lieu va ((cac xuc) or (dat nuoc)) ((va thanh) or (van hanh)) vi van thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty nang x hoi. lieu va ((cac xuc) OR (dat nuoc)) ((va thanh) OR (van hanh)) vi van thiet.
• Adding a wildcard symbol may retrieve word variants: vu sach ty nang x hoi. lieu va ((cac xuc) or (dat nuoc)) ((va thanh) or (van hanh)) vi van thiet*.