Perhaps you should try some spelling variations:
nuoc giai » nuoc ngoai, quoc gia, nuoc thai
truc van » truc va, thuc van, truc ban
hanh de » hanh ve, hanh kem
giai ky » giai ke, giang ky
hieu ve » hieu va, hieu van
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
cu tren » tu tren, dua tren
ve cau » ke cau, va cau, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: nuoc giai ky ((nang ma) OR (tang ma)) hoi. hieu ve cau truc van ((hanh de) or (hanh vi)) cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nuoc giai ky ((nang ma) OR (tang ma)) hoi. hieu ve cau truc van ((hanh de) OR (hanh vi)) cu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nuoc giai ky ((nang ma) OR (tang ma)) hoi. hieu ve cau truc van ((hanh de) or (hanh vi)) cu tren".
• Adding a wildcard symbol may retrieve word variants: nuoc giai ky ((nang ma) OR (tang ma)) hoi. hieu ve cau truc van ((hanh de) or (hanh vi)) cu tren*.