Perhaps you should try some spelling variations:
loai tren » la tren, thai tren
duc van » duc va, duc tan, duc manh
hanh va » hang va, hanh vi
hanh ve » hanh vi, hanh kem
cam duc » cam xuc, cao duc, pham duc
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san

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

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