Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
dao truc » dao tuc, dai truc, vao truc
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
nang xa » nang x, lang xa, nang ma
tai cuu » tai cuc, tai buu, tai cua
cuu tre » cua tre, cau tren, cau treo

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 y) or (sach thu)) nang xa hoi. lieu va ((dao truc) OR (dao tru)) van hanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sach thu)) nang xa hoi. lieu va ((dao truc) OR (dao tru)) van hanh tai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sach thu)) nang xa hoi. lieu va ((dao truc) OR (dao tru)) van hanh tai cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach thu)) nang xa hoi. lieu va ((dao truc) OR (dao tru)) van hanh tai cuu tre*.