Perhaps you should try some spelling variations:
nhanh hai » nhanh thai, thanh hai, nhanh ha
cau tren » cu tren, dau tren, ca tren
nang mai » nang ma, nang tai, lang mai
hieu van » hieu va, thien van, lieu va
hanh hai » thanh hai, hang hai, hanh tai
so sach » so sanh, bo sach, co sach
sach ly » sach y, sach lo, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
ly nang » ky nang, ly hang, ly vang
nam tu » nam thu, nam thuc
cam tu » cam thu, dam tu, tam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ly nang mai hoi. hieu van ((cam tu) or (nam tu)) va ((hanh hai) OR (nhanh hai)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ly nang mai hoi. hieu van ((cam tu) OR (nam tu)) va ((hanh hai) OR (nhanh hai)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ly nang mai hoi. hieu van ((cam tu) or (nam tu)) va ((hanh hai) OR (nhanh hai)) cau tren".
• Adding a wildcard symbol may retrieve word variants: so sach ly nang mai hoi. hieu van ((cam tu) or (nam tu)) va ((hanh hai) OR (nhanh hai)) cau tren*.