Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
thanh dat » thanh san, thanh hai, thanh van
ve chinh » te chinh, va chinh, che chinh
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
va cham » va tham
va chat » van chat, va phat, cao chat

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 ky dang xa hoi. hieu ((ve chinh) or (((va cham) or (va chat)))) thuc vat thanh dat va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang xa hoi. hieu ((ve chinh) OR (((va cham) OR (va chat)))) thuc vat thanh dat va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang xa hoi. hieu ((ve chinh) or (((va cham) or (va chat)))) thuc vat thanh dat va triet*.