Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
hieu van » hieu va, thien van, lieu va
tuan dat » tan dat, tuat dat, thanh dat
tu sach » su sach, te sach, tu cach
nang ma » tang ma, sang ma, nang cao
van cam » van nam, van lam, van cau
xuc van » duc van, luc van, xuc ban
vuc van » duc van, luc van, thuc van
dat hoa » dat khoa, dai hoa, day hoa
ma hoi » mai hoi, xa hoi, ma hoa

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) or (thu sach)) ky nang ma hoi. hieu van cam ((xuc van) OR (vuc van)) tuan dat hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang ma hoi. hieu van cam ((xuc van) OR (vuc van)) tuan dat hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky nang ma hoi. hieu van cam ((xuc van) OR (vuc van)) tuan dat hoa viet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang ma hoi. hieu van cam ((xuc van) OR (vuc van)) tuan dat hoa viet*.