Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cam truc » cau truc, nam truc, lam truoc
hanh tai » thanh tai, hang tai, han tai
sang tao » hang tai
tai cau » tai cac, tai cao
sang ky » sang kyo, dang ky, tang ky
va hanh » van hanh, va thanh, va danh
sang ma » tang ma, nang ma, mang may
truc va » thuc va, thuc vat, trung va
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
san ky » van ky, dan ky, ban ky

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((san ky) OR (sang ky)) ((sang tao) or (sang ma)) hoi. hieu ve cam truc va hanh tai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (sang ky)) ((sang tao) OR (sang ma)) hoi. hieu ve cam truc va hanh tai cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((san ky) OR (sang ky)) ((sang tao) or (sang ma)) hoi. hieu ve cam truc va hanh tai cau tren".
• Adding a wildcard symbol may retrieve word variants: tu ((san ky) OR (sang ky)) ((sang tao) or (sang ma)) hoi. hieu ve cam truc va hanh tai cau tren*.