Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
hanh tai » hang tai, han tai, hinh tai
duc tre » duoc tren, duc tien
hieu ve » hieu va, hieu van
hang ca » hang va, nang cao, hang tai
ly hang » ly quang
cac tu » cac thu, cach tu, cac du
ca hoi » cau hoi, cua hoi, xa hoi
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc cac) OR (hoc cao)) ly hang ca hoi. hieu ve cac tu va ((hanh tai) or (thanh tai)) duc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc cac) OR (hoc cao)) ly hang ca hoi. hieu ve cac tu va ((hanh tai) OR (thanh tai)) duc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc cac) OR (hoc cao)) ly hang ca hoi. hieu ve cac tu va ((hanh tai) or (thanh tai)) duc tre".
• Adding a wildcard symbol may retrieve word variants: ((hoc cac) OR (hoc cao)) ly hang ca hoi. hieu ve cac tu va ((hanh tai) or (thanh tai)) duc tre*.