Perhaps you should try some spelling variations:
va thuat » ky thuat, ki thuat, va thuc
van tham » van thanh, van tuan, van chat
va doanh » van doanh, vay doanh, va danh
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
va tham » va cham, va thanh
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: te sach ky lang xa hoi. hieu ((((va tham) OR (va thuat))) or (van tham)) duc va doanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. hieu ((((va tham) OR (va thuat))) OR (van tham)) duc va doanh tai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang xa hoi. hieu ((((va tham) OR (va thuat))) or (van tham)) duc va doanh tai cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. hieu ((((va tham) OR (va thuat))) or (van tham)) duc va doanh tai cuu tre*.