Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
cac tren » ca tren, cau tren, rac tren
thu sach » thuat sach, thuoc sach, thu hoach
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
cam tuc » cam xuc, nam thuc, dam thuc
vai cac » va cac, tai cac, voi cac
tu sach » su sach, te sach, tu cach
cam tu » cam thu, nam tu, dam tu
x hoi » xa hoi, o hoi, x ho

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 x hoi. hieu van ((cam tuc) OR (cam tu)) va thanh vai cac tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang x hoi. hieu van ((cam tuc) OR (cam tu)) va thanh vai cac tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu sach)) ky nang x hoi. hieu van ((cam tuc) OR (cam tu)) va thanh vai cac tren".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang x hoi. hieu van ((cam tuc) OR (cam tu)) va thanh vai cac tren*.